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10 Common Web Security Vulnerabilities

  • By Gcore
  • July 18, 2023
  • 12 min read
10 Common Web Security Vulnerabilities

Companies today rely heavily on websites and web applications to communicate with their employees, partners, and clients across different locations and time zones. However, this increase in digital communication comes with an increased risk of cybercrime. It is crucial for businesses to understand the potential web security vulnerabilities in their IT systems and take proactive measures to safeguard sensitive assets. This post provides an overview of cybercrime, and then explores the top 10 web security vulnerabilities of which you should be aware in detail.

What Are Web Security Vulnerabilities?

Web security vulnerabilities are weaknesses or misconfigurations in a web application that an attacker can exploit to gain unauthorized access or perform unauthorized, malicious actions. These vulnerabilities act like open windows in a house, enabling unauthorized access. Web security vulnerabilities can exist in various parts of a web application, including the server, host, or application software itself. Web applications interact with users across various networks, making them attractive targets for hackers.

When web application vulnerabilities are exploited, businesses are at risk of cybercrime, meaning that potential threats exist to the confidentiality, integrity, and availability of their data and services. For example, these attacks often intend to steal valuable sensitive information, such as personal data, intellectual property, or financial details, and comprise the data stored in the system as a whole. Cybercrime can result in fraud (like identity theft,) holding businesses to ransom for their data, or undermining trust in a service provider.

To grasp the gravity of web security vulnerabilities, we need to consider three key factors: exploitability, detectability, and potential impact.

Exploitability

Exploitability refers to the level of ease with which an attacker can take advantage of a security vulnerability. At one end of the spectrum, an attack may only require a web browser, making it highly exploitable. At the other end, advanced programming skills and tools are necessary, resulting in low exploitability.

Detectability

Detectability plays a vital role in identifying security threats. The higher the detectability, the easier it is to recognize a vulnerability. Information displayed in the URL, forms, or error messages provides clues that aid in vulnerability identification, offering a high level of detectability. Conversely, low detectability involves delving into the source code, demanding advanced knowledge and expertise. For example, a vulnerable web application that leaks sensitive user data via a poorly implemented authentication mechanism can be easily identified through error messages or anomalies in the URL structure.

Potential Impact

Assessing the potential impact or damage caused by a security vulnerability is key. A highly impactful vulnerability can result in a complete system crash, leading to significant disruptions and potential data breaches. Consider an SQL injection vulnerability that allows attackers to manipulate database queries. Exploiting this vulnerability can lead to unauthorized access, data theft, or even the modification of critical information, causing severe consequences. On the other hand, a vulnerability with low impact may not cause any damage at all.

By understanding exploitability, detectability, and potential impact, organizations can effectively evaluate the risks associated with web security vulnerabilities. Armed with this understanding, appropriate measures can be implemented in a timely manner to mitigate these risks.

10 Common Web Security Vulnerabilities

To effectively address web security, it is crucial to have a comprehensive understanding of the common vulnerabilities that can be exploited by attackers. You can only fix what you can first identify! These vulnerabilities often stem from flaws in the design, implementation, or configuration of web applications.

#1 Broken Access Control

How broken access control can be exploited in a cyber attack

Broken access control is a critical security vulnerability that occurs when users can access data or resources that they should not have permission to access. This breach in access control can arise due to various factors, including poor permissions management, weak authentication mechanisms, or misconfigured security controls. Let’s look at each in turn.

Poor Permissions Management

Poor permissions management is a common cause of broken access control. When permissions are not properly configured, users may gain access to sensitive data or resources that should be restricted. This can happen when access privileges are inaccurately assigned, leading to unintended exposure of sensitive information. Inconsistencies in permission settings across different parts of an application can also contribute to this vulnerability, allowing unauthorized users to bypass access restrictions.

Weak Authentication Mechanisms

Weak authentication mechanisms play a significant role in broken access control. If authentication mechanisms are not robust, attackers can exploit these weaknesses to gain unauthorized access to a system. Weak passwords, lack of multi-factor authentication (MFA,) or ineffective session management can all contribute to the vulnerability. For example, if a user chooses a weak password or if password complexity requirements are not enforced, it becomes easier for attackers to guess or crack passwords and gain unauthorized access to user accounts.

Misconfigured Security Controls

Misconfigured security controls is another web security vulnerability that can lead to broken access control. When security controls are not properly configured, attackers may find ways to bypass these measures and gain unauthorized access. This can occur when security configurations are left at default settings, which might not provide adequate protection. Misconfigurations in firewall rules, access control lists, or other security components can also create loopholes that allow unauthorized access.

Mitigating Broken Access Control

Mitigating broken access control requires implementing proper access control mechanisms, strong authentication practices, and vigilant security configurations. Access permissions should be carefully defined and regularly audited to ensure that users can only access the data and resources they are authorized to. Robust authentication mechanisms, such as strong passwords, multi-factor authentication, and secure session management, should be implemented to prevent unauthorized access. Additionally, security controls and configurations should be reviewed and updated regularly to address any vulnerabilities or misconfigurations.

#2 Cryptographic Failures

An attacker can gain access to a users’ credentials across multiple websites by exploiting cryptographic failures in an app to access password data

A cryptographic failure refers to a web security vulnerability through which the implementation or usage of cryptographic measures fails to provide the intended level of security, which can compromise the confidentiality, integrity, or availability of the data that the cryptography was supposed to protect. Cryptographic failures pose a significant security risk when sensitive data is not properly encrypted or when cryptographic keys are mishandled. These vulnerabilities can result in severe consequences, including data breaches and identity theft.

Insecure Storage of Cryptographic Information

One prevalent cryptographic vulnerability is the insecure storage of cryptographic information. This vulnerability arises when sensitive data is stored in an insecure manner, leaving it vulnerable to exploitation. For instance, sensitive data like user credentials, profile information, health details, and credit card information all require protection. However, if this data is improperly stored without adequate encryption or proper hashing techniques, it becomes an attractive target for malicious actors.

Consider a scenario where a web application stores user passwords in plain text or uses weak encryption algorithms. In the event of a security breach, attackers can gain unauthorized access to the application’s database and easily retrieve and exploit the stored passwords. This can have devastating consequences, including unauthorized account access, identity theft, and the compromise of other systems or services where users reuse passwords.

The implications of this web security vulnerability are far reaching. Exploiting this vulnerability allows attackers to steal or modify weakly protected data, leading to identity theft, credit card fraud, and other criminal activities. The primary vulnerable object in this scenario is the application database where the data is stored. Such activities can cause financial losses, damage reputations, and even result in legal consequences.

#3 Injection Flaws

Injection flaws happen when an attacker injects malicious data into a command or query that is then processed by an application. These flaws occur when an application sends untrusted data to an interpreter or a service without properly validating or sanitizing the input first. The malicious data can lead the interpreter or service to execute unintended commands, leading to data loss, corruption, or unauthorized access.

SQL Injection

SQL injection is a widespread security vulnerability that occurs when a hacker injects malicious SQL code into a web application, enabling unauthorized access to sensitive data or control over the affected system. This type of attack poses a significant threat, often resulting in the compromise of e-commerce websites and the illegal retrieval of valuable information such as user details, credit card data, and social security numbers.

To safeguard against SQL injection, ensure that your SQL database is appropriately configured. Employ best practices such as using parameterized queries or prepared statements, as they help prevent attackers from manipulating SQL statements. Regularly update your devices with the latest security patches, as software updates often address known vulnerabilities that can be exploited by attackers.

Other Injection Vulnerabilities

Injection vulnerabilities are not limited to SQL injection. Other forms of injection vulnerabilities, such as LDAP injection or Cross-Site Scripting (XSS) can also pose significant risks. To protect against these types of vulnerabilities, it is crucial to implement input filtering and validation mechanisms. Any untrusted input received by your application should undergo thorough filtering, preferably using a whitelist approach. This ensures that only expected and validated input is accepted, effectively preventing attackers from injecting malicious code or scripts. Relying solely on blacklists can be challenging to configure effectively and may be circumvented by skilled attackers.

To mitigate the risk of injection vulnerabilities, implement robust user authentication tools, Strong authentication mechanisms (such as enforcing complex passwords and utilizing multi-factor authentication) to help prevent unauthorized access to sensitive data, and restrict access privileges based on the principle of least privilege. The latter ensures that users only have access to the resources they require to perform their tasks, reducing the potential impact of an attack.

#4 Insecure Direct Object References

Insecure direct object references (IDOR) vulnerabilities arise when a web application exposes internal objects, such as files, directories, or database keys, through URLs or form parameters. These vulnerabilities stem from blindly trusting user input, which can lead to unintended exposure of sensitive information. Exposure of the internal objects can enable attackers to gain unauthorized access to other objects that were not initially exposed, and potentially compromise the application’s data integrity.

Examples and Implications of IDOR Vulnerabilities

The implications of IDOR vulnerabilities are significant, as attackers can exploit them to access unauthorized internal objects, manipulate data, or compromise the overall security of the application. For example, consider a download module that allows file downloads without proper authorization checks. If this module exposes the file path within the URL, an attacker could modify the URL to access other system files that should be restricted. This can result in unauthorized access to sensitive data, compromising the confidentiality and integrity of the application.

Similarly, insecure direct object references in password reset functions can be exploited by attackers to manipulate privileged accounts. If the password reset functionality exposes user account information within the URL or form parameters, an attacker could tamper with the values to gain unauthorized access to privileged accounts. This can lead to unauthorized actions, data breaches, and potential damage to the overall security of the application.

#5 Server-Side Request Forgery (SSRF)

Depiction of a legitimate HTTP request from an attacker that includes an SSRF payload, which triggers malicious requests across connected networks

Server-side request forgery (SSRF) is a specific type of attack that exploits a distinct vulnerability. SSRF vulnerabilities occur when a web application fails to properly validate user-provided URLs when accessing remote resources. Attackers can manipulate vulnerable applications to send crafted requests to specific URLs, bypassing access controls like firewalls that would typically block direct connections to the target URL but grant access to the compromised web application.

One case of an SSRF vulnerability is the unauthorized retrieval of sensitive data from an internal database through a vulnerable web application. By carefully exploiting the SSRF vulnerability, an attacker can deceive the application into making requests to internal URLs, ultimately gaining access to confidential information. Proper input validation and robust security measures are essential for web applications to mitigate the risk of SSRF attacks.

One recent example highlighting the impact of SSRF vulnerabilities is the Capital One hack. In this incident, 140,000 Social Security numbers and 80,000 bank account numbers were stolen. The attack exploited an SSRF vulnerability that allowed the attacker to gain unauthorized access to sensitive information. Remarkably, the incident remained undetected for four months, emphasizing the significance of identifying and addressing SSRF vulnerabilities promptly and effectively.

#6 Cross-Site Request Forgery (CSRF)

Diagram depicting how cross-site request forgery (CSRF) attacks work across multiple tabs in the same browser by exploiting a users’ one-time log-in

Cross-site request forgery (CSRF) is an attack in which a malicious entity deceives a user’s browser into performing actions on a trusted website without their knowledge or consent. This type of attack occurs when the user is already authenticated on the targeted site. By forging a request with the user’s session cookie and other authentication information, the attacker can carry out unauthorized actions, potentially compromising the victim’s account.

The implications of a CSRF vulnerability are severe. Attackers can manipulate user profile information, change status updates, or even create new users on behalf of administrators. Certain objects within a web application, such as user profile pages, user account forms, and business transaction pages, are particularly vulnerable to CSRF attacks.

CSRF in E-commerce

To understand the potential impact of a CSRF vulnerability, consider a scenario where a victim is logged into a frequently used e-commerce website. Unbeknownst to them, simply browsing the web without first logging out can enable a cybercriminal to trick the browser into making purchases on a different website they visit, without their consent. By embedding malicious code into that website, the hacker can utilize the victim’s saved payment information and complete a purchase using their account.

#7 Outdated or Vulnerable Web Application Components

An attacker can use vulnerable and outdated internal components to carry out a cyber attack

The use of outdated or vulnerable components in web applications can pose significant security risks. In recent years, the emergence of supply chain vulnerabilities has magnified these concerns. Threat actors deliberately inject malicious or vulnerable code into widely used libraries and third-party dependencies, creating a potential entry point for attackers. Organizations that lack visibility into their external code and fail to promptly apply necessary security updates expose themselves to significant risks.

Real-world incidents have demonstrated the dire consequences of neglecting to update third-party software. For instance, outdated WordPress plugins that remained unpatched in environments for prolonged periods led to severe security breaches. Attackers exploited these vulnerabilities to gain unauthorized access and compromise entire systems, resulting in data breaches, service disruptions, and reputational damage.

It is essential to recognize that software development goes beyond initial deployment. It requires meticulous documentation, rigorous testing, and effective maintenance plans, particularly when utilizing third-party or open-source components. Proactive steps should be taken to assess web applications for vulnerable and outdated components during the maintenance and deployment stages of development.

#8 Security Misconfigurations

Security misconfigurations are when a component of a system is not set up correctly, leading to potential vulnerabilities that can be exploited by cyberattackers, exposing organizations to risks of unauthorized access and data breaches, also allowing the attacker to gather critical information about the application for further attacks.

Alarming industry reports indicate that up to 95% of security breaches stem from human error, implementing proper security configurations incorrectly. This highlights the critical role that comprehensive security practices play in preventing incidents. One prevalent cause of security misconfigurations is the failure to regularly update and patch systems, frameworks, and components, leaving them exposed to known vulnerabilities.

Implications of Security Misconfigurations

The implications of security misconfigurations are severe, as they provide attackers with opportunities to identify the underlying technology, access sensitive information, and potentially compromise the entire system. For example, leaving an application server’s admin console with default settings and unchanged passwords creates an easily exploitable entry point for unauthorized access. Similarly, enabling directory listing on the server inadvertently exposes valuable files and directories to potential attackers.

#9 Unvalidated Redirects and Forwards

Unvalidated redirects and forwards (URF) present security vulnerabilities in web applications. These vulnerabilities arise when applications redirect or forward users to URLs supplied by the users themselves. Attackers exploit URF vulnerabilities to redirect users to malicious sites, leading to data theft, malware installation, and other harmful actions. These vulnerabilities occur when developers fail to properly validate user input, enabling attackers to inject malicious code into URLs or query strings.

Examples of URF

Improper configuration of web applications can also contribute to URF vulnerabilities. For example, the use of insecure random number generators in web applications can facilitate the manipulation of URLs or query strings by attackers. They can predict and manipulate these parameters, redirecting users to malicious sites without their knowledge or consent.

To give another example, imagine a website’s redirect.php module accepts a URL as a parameter, which can be manipulated to deceive users with seemingly safe links that actually lead to malicious destinations. Users may unknowingly provide sensitive information or fall victim to malware or phishing attacks. Implementing input validation and strict rules for user-supplied URLs can mitigate URF vulnerabilities, ensuring user safety and protecting against unauthorized redirects.

#10 Software and Data Integrity Failures

How attackers can use software failures to exploit legitimate users and undermine the code of an application

Software and data integrity failures refer to vulnerabilities in web security that take place when the integrity of critical data and software updates is not verified before they are added to the delivery pipeline. These failures can result from faulty assumptions, outdated software, insufficient vulnerability scanning, erroneous input validation, missing patches, missing unit tests, or insecure component configurations.

In today’s agile software development landscape, where rapid updates are common, the lack of strict integrity checks poses a serious risk. These failures can have far-reaching impacts, including unauthorized information disclosure, system compromise, and the insertion of malicious code. Attackers can exploit these vulnerabilities by injecting malicious inputs, which can impact various stages of the deployment pipeline.

Insecure Deserialization

Insecure deserialization is a common manifestation of software and data integrity failures. Attackers can tamper with input payloads during deserialization, coercing the application to execute malicious code or alter its logic. Another example is the reliance on unvalidated cookies. Applications often use cookies for security controls, but without proper integrity checking, hackers can modify cookies to supply malicious input, perform injection attacks, or bypass authentication.

What Are the Repercussions of Web Security Vulnerabilities?

Cybercrime can have severe consequences for businesses that become victims. The repercussions may include damage to the company’s reputation, loss of customer trust, financial losses, and potential legal issues. It is crucial to understand the gravity and type of these threats and take proactive steps to mitigate them.

How Can You Protect Your Business Against Web Security Vulnerabilities?

Implementing web security measures is essential to reduce vulnerabilities and defend against potential attacks. Waiting until a breach occurs is not an effective strategy. On average, it takes 287 days to detect and contain a single data breach. Adopting a proactive approach to data protection is crucial to save time, optimize resources, and safeguard valuable company assets.

Begin by conducting a comprehensive web security assessment. This assessment should encompass evaluation of vulnerabilities in your systems, networks, and applications, focusing on areas including data storage, access controls, encryption, and employee awareness. By identifying and addressing these vulnerabilities, you can enhance your overall security posture and protect your business from cybercrimes.

Conclusion

As organizations embrace the accelerating power of web-based communication, it is essential to prioritize the security of the valuable information held therein. By understanding and addressing common web security vulnerabilities, organizations can fortify their defenses and safeguard against online threats.

The path to effective cybersecurity involves taking proactive measures to counter the ten common web security vulnerabilities discussed here. Examples of such proactive cybersecurity measures include regular security updates and patching, robust authentication mechanisms, secure coding practices, thorough input validation, strict configuration management, and comprehensive security testing. Staying informed about emerging threats, promoting security awareness among employees, and maintaining a culture of vigilance are vital for maintaining a strong defense against evolving web security risks. By prioritizing web security, organizations can protect their sensitive data, maintain customer trust, and preserve their reputation in an increasingly interconnected digital landscape.

At Gcore, we understand the critical importance of choosing the right cybersecurity tools to protect your digital assets. Gcore’s Web Application Security is a comprehensive, all-in-one solution. It includes a Web Application Firewall (WAF) with a built-in ML mechanism that continuously checks reliability and identifies potential vulnerabilities. Let us take care of your web application security so you can focus on your business goals.

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The web is a public infrastructure: Anyone can use it. Encryption is a must to ensure that communications over this public infrastructure are secure and private. You don’t want anyone to read or modify the data you send or receive, like credit card information when paying for an online service.TLS encryption is a basic yet crucial safeguard that ensures only the client (the user’s device, like a laptop) and server can read your request and response data; third parties are locked out. You can run TLS on a CDN for improved performance, caching, and TLS management. If you want to learn more about TLS and how running it on a CDN can improve your infrastructure, this is the right place to start.What Is TLS Encryption and Why Does It Matter?TLS, transport layer security, encrypts data sent via the web to prevent it from being seen or changed while it’s in transit. For that reason, it’s called encryption in-transit technology. TLS is also commonly called HTTPS when used with HTTP or SSL, as previous versions of the technology were based on it. TLS ensures high encryption performance and forward secrecy. To learn more about encryption, check out our dedicated article.TLS is a vital part of the web because it ensures trust for end users and search engines alike. End users can rest assured that their data—like online banking information or photos of their children—can’t be accessed. Search engines know that information protected by TLS is trustworthy, so they rate it higher than non-protected content.What’s the Connection Between TLS and CDN?A CDN, or content delivery network, helps improve your website’s performance by handling the delivery of your content from its own servers rather than your website’s server. When a CDN uses TLS, it ensures that your content is encrypted as it travels from your server to the CDN and from the CDN to your users.With TLS offloading, your server only needs to encrypt the content for each CDN node, not for every individual user. This reduces the workload on your server.Here’s a simple breakdown of how it works:Your server encrypts the content once and sends it to the CDN.The CDN caches this encrypted content.When a user requests the content, the CDN serves it directly to them, handling all encryption and reducing the need to repeatedly contact your server.Without a CDN, your server would have to encrypt and send content to each user individually, which can slow things down. With a CDN, your server encrypts the content once for the CDN. The CDN then takes over, encrypting and serving the content to all users, speeding up the process and reducing the load on your server.Figure 1: Comparison of how content is served with TLS on the web server (left) vs on CDN (right)Benefits of “Offloading” TLS to a CDNOffloading TLS to a CDN can improve your infrastructure with improved performance, better caching, and simplified TLS management.Increased PerformanceWhen establishing a TLS connection, the client and server must exchange information to negotiate a session key. This exchange involves four messages being sent over the network, as shown in Figure 2. The higher the latency between the two participants, the longer it takes to establish the connection. CDN nodes are typically closer to the client, resulting in lower latency and faster connection establishment.As mentioned above, CDN nodes handle all the encryption tasks. This frees up your server’s resources for other tasks and allows you to simplify its code base.Figure 2: TLS handshakeImproved CachingIf your data is encrypted, the CDN can’t cache it. A single file will look different from the CDN nodes for every new TLS connection, eliminating the CDN benefits (Figure 3). If the CDN holds the certificates, it can negotiate encryption with the clients and collect the files from your server in plaintext. This allows the CDN to cache the content efficiently and serve it faster to users.Figure 3: TLS and CDN caching comparedSimplified TLS ManagementThe CDN takes care of maintenance tasks such as certificate issuing, rotation, and auto-renewal. With the CDN managing TLS, your server’s code base can be simplified, and you no longer need to worry about potential TLS updates in the future.TLS Encryption with Gcore CDNWith the Gcore CDN we don’t just take care of your TLS encryption, but also file compression and DNS lookups. This way, you can unburden your servers from non-functional requirements, which leads to smaller, easier-to-maintain code bases, lower CPU, memory, and traffic impact, and a lower workload for the teams managing those servers.Gcore CDN offers two TLS offloading options:Free Let’s Encrypt certificates with automatic validation, an effective and efficient choice for simple security needsPaid custom certificates, ideal if your TLS setup has more complex requirementsHow to Enable HTTPS with a Free Let’s Encrypt CertificateSetting up HTTPS for your website is quick, easy, and free. First, make sure you have a Gcore CDN resource for your website. If you haven’t created one yet, you can do so in the Gcore Customer Portal by clicking Create CDN resource in the top-right of the window (Figure 4) and following the setup wizard. You’ll be asked to update your DNS records so they point to the Gcore CDN, allowing Gcore to issue the certificates later.Figure 4: Create CDN resourceNext, open the resource settings by selecting your CDN resource from the list in the center (Figure 5).Figure 5: Select the CDN resourceEnable HTTPS in the resource settings, as shown in Figure 6:Select SSL in the left navigationClick the Enable HTTPS checkboxClick Get SSL certificateFigure 6: Get an SSL certificateYour certificate will usually be issued within 30 minutes.Our Commitment to Online SecurityAt Gcore, we’re committed to making the internet secure for everyone. As part of this mission, we offer free CDN and free TLS certificates. Take advantage and protect your resources efficiently for free!Get TLS encryption on Gcore CDN free

How to Detect and Stop Bad Bots

A bot, short for “robot,” is a software program that can perform tasks automatically, quickly, and efficiently. Both good bots and bad bots exist; Googlebot facilitates web page indexing, but LizardStresser orchestrates DDoS attacks. Because good and bad bots share certain traits, distinguishing between them can be tricky unless the correct bot detection techniques are used. In this article, we examine the evolution of bot detection techniques in response to the ever-changing threat landscape and discuss how bots can be detected and, when desirable, stopped.What Is Bot Detection?Bot detection is the process of identifying and distinguishing between legitimate human users, good bots, and bad bots. Because bots can mimic certain legitimate user behaviors, such as mouse movements and keystrokes, cybersecurity professionals and business leaders should implement bot detection as an integral component of their security strategy. Otherwise, you could end up with misleading analytics, compromised user experiences, and potential security breaches that can harm your organization’s reputation and bottom line.Bot detection helps to mitigate malicious bot activities such as unethical web scraping, spamming, account takeover, click fraud, and DDoS attacks, without interfering with good bots such as website uptime monitors. Effective bot detection enhances cybersecurity and improves the web user’s overall experience.Botnet Detection TechniquesOver the decades, different botnet mitigation techniques have been developed to deal with the challenges of stopping bad bots while allowing good bots to continue their activities. These techniques typically involve identifying the command-and-control infrastructure coordinating the botnet activities. However, since botnets keep evolving to bypass mitigation measures, new and better botnet detection and mitigation strategies are continuously being developed.Let’s examine botnet detection techniques. We’ll start with the oldest and then look at contemporary techniques. However, new techniques build on the old, and all these techniques still play a part in botnet detection today.Intrusion Detection SystemsFigure 1: How a basic intrusion detection system worksIntrusion detection systems (IDS) emerged in the late 1980s to monitor and analyze network traffic for security incidents like unauthorized access and policy violations. IDS can detect threats, such as botnets, and alert security teams. Intrusion prevention systems (IPS) can proactively mitigate detected threats. Modern IDPS (intrusion detection and prevention systems) combine IDS and IPS functions.IDS is trained on data from sources like network traffic, system logs, and application activity. Botnet-focused IDS can be anomaly-based (monitoring abnormal behaviors) or signature-based (matching patterns with known botnets).When a potential botnet is detected, the IDS generates alerts or notifications based on severity. Depending on cybersecurity policies, the IDS may block traffic, isolate systems, or alert security teams. IDS also generates incident logs and reports, detailing the time of incidents, detected threats, countermeasures, and recommendations for improvement.Intrusion detection systems can be grouped into six types:Network-Based Intrusion Detection Systems (NIDS): These monitor real-time network traffic and analyze packets on network segments or devices to detect attacks like DoS, port scanning, and reconnaissance.Protocol-Based Intrusion Detection Systems (PIDS): A type of NIDS that targets specific network communication protocols (e.g., P2P, HTTP, IRC) to protect against intrusion and policy violations. PIDS is limited in scope.Machine Learning-Based Intrusion Detection Systems (ML-IDS): Subset of NIDS using machine learning algorithms to detect network intrusions and malicious activities by learning from historical data. ML-IDS is more efficient than traditional rule-based systems but requires fine-tuning to minimize false positives.Host-Based Intrusion Detection Systems (HIDS): Monitor the computer infrastructure they are installed on (e.g., computers, servers) to safeguard against attacks. They gather data, analyze traffic, and log suspicious behavior, providing insights into system health and security. HIDS is an approach that’s most suitable for small teams with lean overheads.Hybrid Intrusion Detection Systems: Combine different detection techniques (e.g., NIDS, HIDS, anomaly-based, signature-based) in a single framework to effectively detect botnet activity and provide insightful data. Problematically, they create a single point of failure and are complex to troubleshoot.Multi-Layered Intrusion Detection Systems: These systems combine different detection techniques (e.g., NIDS, HIDS, anomaly-based, signature-based) in a layered approach, with each IDS as a separate component. They eliminate a single point of failure and simplify troubleshooting but complicate setup, management, and reporting.To summarize, intrusion detection systems (IDS) enhance network security by monitoring and analyzing traffic to detect potential threats, providing valuable insights and real-time response capabilities. However, they can produce false positives, require ongoing maintenance and fine-tuning, and may be complex to manage and integrate into existing security frameworks.HoneynetFirst used around the year 2000, a honeynet is a network of traps or decoy networks (honeypots) set up with built-in vulnerabilities to attract cyberattacks. A typical honeynet comprises two or more honeypots. Honeynets aid in botnet detection by deliberately exposing vulnerabilities that attract malicious attacks. This deception technique allows botnet attacks to be studied in a controlled environment or managed and stopped, as needed.Figure 2: Honeynet setupAs such, there are two main types of honeynets: research honeynets and production honeynets. Research honeynets are primarily set up to study attack vector tactics, techniques, and procedures, while production honeynets are deployed within production environments.Despite their effectiveness, honeynets have limitations, such as setup complexity, limited network coverage, and high maintenance overhead, especially for high-capacity setups. Additionally, honeynets can sometimes be detected, bypassed, armed, and deployed against the production network itself.DNS-Based Botnet DetectionFigure 3: DNS-based botnet detectionAround 2005, the DNS-based botnet detection technique started to gain popularity. DNS-based botnet detection works by monitoring the way computers use the Domain Name System (DNS) to find websites. When you enter a website address into your browser, your computer uses DNS to find the numerical IP address that corresponds to that website. Botnets, which are networks of infected computers controlled by cybercriminals, often need to communicate with the attackers’ servers to receive instructions. They use DNS to find these servers.A botnet detection system monitors all DNS requests made by network computers. They analyze which domain names are being requested and how often. Since botnets often use unusual domain names that people don’t typically visit, the systems look for patterns that indicate suspicious activity, such as frequent requests to these strange or newly created domains. They can then block the requests to these malicious domains, preventing the infected computers from communicating with the cybercriminals.Although they provide real-time detection, network-wide coverage, low false-positive rates, and threat intelligence gathering, they are prone to evasion techniques and are limited by their reliance on external threat intelligence sources for domain reputation data.Comparison of Botnet Detection TechniquesHere’s how these three botnet detection techniques compare.FeatureIntrusion Detection Systems (IDS)HoneynetDNS-Based Botnet DetectionDefinitionNetwork security tools monitor and analyze network traffic for potential threatsNetwork of traps or decoy networks designed to attract cyberattacksTechnique monitoring and analyzing DNS traffic for botnet activityDetection focusNetwork traffic, system logs, and application activityCyberattackers’ behavior and tacticsDNS traffic patterns, requests, and responsesDetection methodsSignature-based, anomaly-based, machine learningDeception through vulnerabilitiesDomain reputation checks, anomaly detectionData collectedNetwork traffic, system logs, application activityAttack interactions with honeypotsDNS traffic, requests, responsesAlerting and responseGenerates alerts, blocks traffic, isolates systemsStudies attacks, handles malicious interactionsBlocks connections, redirects to sinkholes, alertsUse casesPrevents unauthorized access, breaches, policy violationsStudies attack tactics, gathers threat intelligenceReal-time botnet detection, low false positivesComplexityVaries based on IDS type (NIDS, HIDS, hybrid, multi-layered)Moderate to high due to setup and maintenanceModerate, relies on DNS traffic analysisEffectivenessEffective for detecting network-based threatsEffective for studying attacks, gathering threat intelEffective for real-time botnet detectionLimitationsCan be bypassed by sophisticated attacksSetup complexity, limited network coverageProne to evasion techniques, reliance on external dataDeploymentNetwork-wide, host-based, hybrid, multi-layeredControlled environment, production networksDNS infrastructure monitoringPopularityWidely used in cybersecurityLess common due to complexityIncreasing popularityFuture evolutionEvolving to integrate AI, threat intelligenceEvolving to address evasion techniquesEvolving to handle DNS tunnelingManagement overheadVaried based on IDS type and deploymentHigh for setup, maintenance, and monitoringModerate for DNS traffic analysisHow to Stop BotnetsNow we know how undesirable botnets are detected, let’s turn to how they can be stopped. Three main options exist: CAPTCHA, rate limiting, and bot protection.A. JS Challenges/CAPTCHAOne way to stop bad bot activity is by implementing JS Challenges and CAPTCHA on your websites or web applications. Both are effective security mechanisms used to protect against malicious bots, automated scripts, and other unauthorized automated activities, such as web scraping.Figure 4: CAPTCHAGcore provides JS Challenge and JS CAPTCHA solutions as part of Gcore WAAP. First, a JS challenge runs a small piece of JavaScript code in the user’s browser, which a bot typically cannot execute. This code checks for typical human behavior and browser characteristics to ensure the request comes from a legitimate user. Next, a CAPTCHA presents a task that is easy for humans but difficult for bots, such as identifying objects in images or solving simple puzzles. By completing these tasks, users prove they are human, thereby preventing automated systems from accessing or abusing web services.But there’s a downside: CAPTCHAs do not distinguish between beneficial bots (such as search engine crawlers or monitoring tools) and malicious bots. They can impede good bots from performing their intended functions. To allow good bots while still protecting against malicious ones, website administrators need to create exceptions or use alternative verification methods that can recognize and permit trusted bots. Gcore manages this process with our WAAP customers to ensure good bots continue to function effectively.B. Rate LimitingFigure 5: Rate LimitingA key characteristic of bots is their ability to automate and rapidly scale tasks. For example, bots can fill and submit forms much faster than humans, sending a large number of requests to the server and receiving an equally large number of responses. This can drain server resources and degrade site performance.Rate limiting controls the number of requests an IP address or IP range can make to a resource within a certain timeframe. This method mitigates bad bot activity on websites or web applications. Good bots don’t engage in this kind of behavior, so there’s not much risk of stopping their activity with a rate limiter.Gcore Rate Limiter protects your websites and web applications from excessive requests that signal bad bot activity. You can specify a set of rules dictating how many requests are allowed per IP address per second. Once this limit is exceeded, the requester will receive an HTTP 429 (Too Many Requests) error message.Stop Bad Bots with Gcore WAAPWhile bot detection techniques such as honeynets, DNS-based bot detectors, and intrusion detection systems (IDSs) are effective in their own right, a hybrid or multi-layered bot detection approach is the most accurate way to detect bot activity. Gcore WAAP (Web Application Firewall + API Protection) is the ultimate all-in-one bot detection and protection solution for your websites and web applications. Gcore WAAP incorporates bot protection with a web application firewall, API security, and advanced DDoS protection to offer enhanced enterprise-grade security.We protect against threats including and beyond the OWASP Top 10, addressing unpatched vulnerabilities and zero-day attacks by leveraging machine learning technologies. With Gcore WAAP, you enjoy API-specific protection and security against credential stuffing, account takeover, brute force attacks, and L7 DDoS attacks.Gcore WAAP is scalable to meet your needs, regardless of industry. It is also easy to deploy—no additional hardware, software, or changes in the code are required on your part. Once you send a request, Gcore will start protecting your web resources immediately. Request Gcore WAAP today and enjoy bot-free websites and web applications.ConclusionDetecting and stopping bad bots involves a combination of advanced techniques tailored to identify and mitigate malicious activities while allowing beneficial bots to operate. Implementing a multi-layered bot detection strategy, such as Gcore WAAP, ensures comprehensive protection against various threats while maintaining website performance and user experience.Gcore WAAP is integrated into Gcore’s global infrastructure, operating on 180+ global points of presence in Tier III and IV data centers, ensuring optimal performance, low latency worldwide, and outstanding security at the network’s edge. Secure your web applications and APIs against the most sophisticated cyber threats to safeguard your business’ reputation.Discover Gcore WAAP

What Is TCP DDoS Protection? | How Does It Work?

TCP DDoS (distributed denial-of-service) attacks pose a significant threat to network infrastructure. They exploit vulnerabilities in the TCP protocol to overwhelm servers and disrupt legitimate traffic. This article explains the mechanics of TCP DDoS attacks, their potential impact, and effective strategies for prevention and mitigation. We’ll explore different types of TCP DDoS attacks, such as SYN floods and ACK floods, and discuss how to safeguard your systems against these threats using techniques like SYN cookies, traffic filtering, and load balancing.What Is a TCP DDoS Attack?A TCP DDoS attack (Transmission Control Protocol distributed denial-of-service) is a type of cyberattack that targets the TCP protocol, a fundamental communication protocol used in networked systems. DDoS attacks aim to disrupt normal traffic on a network by overwhelming it with a flood of malicious traffic.In a TCP DDoS attack, the attacker uses multiple compromised devices, often referred to as a botnet, to send a huge number of packets (small units of data) to a target network or server. The goal is to overload the network components, making them unable to handle legitimate requests from real users.The principle of a DDoS attackTCP is widely used for internet communications, including web browsing and email, but it wasn’t originally designed with robust security features. This lack of built-in security makes it vulnerable to exploitation. Hackers can send different types of TCP packets to execute their attacks. To understand this, let’s examine how TCP normally functions and what happens during a DDoS attack in the three most common TCP attack methods.How Does a TCP DDoS Attack Work?When a device, like your computer, wants to connect to a server, such as a website, it follows a three-step process known as the TCP handshake.How TCP normally worksEach type of TCP DDoS attack (SYN flood, SYN-ACK flood, and ACK flood) targets a different stage of this handshake. By overwhelming the server at each stage, the attacker disrupts the handshake process, causing downtime and service disruption for legitimate users.Let’s look at how TCP works and how different types of attacks exploit each stage.Initiating the Connection: SYN FloodNormal process: Your device sends a SYN packet to the server to request a connection.SYN flood attack: The attacker sends a massive number of SYN packets to the server, pretending to request connections. The server tries to respond to each request by sending SYN-ACK packets. However, since the attacker never completes the handshake, the server is left waiting with numerous half-open connections, consuming its resources and making it unable to handle legitimate requests.In an SYN flood attack, the attacker can use their own resources to send the requests or use TCP/IP hijacking to spoof legitimate IP addresses, making the malicious requests appear genuine. The spoofed systems do not respond to the SYN-ACK packets because they are unaware of the SYN packets sent on their behalf. Even though the server eventually drops these half-open connections, the sheer volume can exceed the server’s capacity, rendering it unresponsive to real clients.How a SYN flood attack worksAcknowledging the Request: SYN-ACK FloodNormal process: The server receives the SYN packet and responds with a SYN-ACK packet to acknowledge the connection request.SYN-ACK flood attack: The attacker sends a large number of SYN-ACK packets to the server without any corresponding SYN requests. The server has to process these unexpected packets, which uses up its resources and disrupts its ability to function properly.A SYN-ACK flood leverages an unusual approach by sending SYN-ACK packets to the server. Even though they are not part of a legitimate handshake, these packets must be processed, and a significant number of such packets can cause server-side disruptions.Completing the Handshake: ACK PacketsNormal process: Your device responds to the server’s SYN-ACK packet with an ACK packet, completing the handshake and establishing the connection.ACK flood attack: The attacker sends a flood of ACK packets to the server. These packets look like legitimate responses, so the server spends its resources processing them. This overwhelms the server, making it difficult for it to handle actual connections from real users.An ACK flood exploits the TCP function for data delivery acknowledgment. When a client receives the requested data, it sends an ACK message to inform the server that the data was successfully received. Attackers take advantage of this by sending a large number of forged ACK packets, which look identical to legitimate ones. This overwhelms the server, as it cannot distinguish between real and fake ACK messages, leading to resource exhaustion and service disruption.What Damage Can a TCP DDoS Attack Cause?A successful TCP DDoS attack overwhelms the target server with fake requests, rendering the server unavailable to real users and the services relying on it. The duration of the downtime and the criticality of the affected services can result in significant financial losses and reputational damage for the business. Unprotected businesses lose an average of $6,000 per minute during a DDoS attack. The unavailability of an online banking service or a medical institution can cause real distress and disruption with serious consequences for customers.DDoS attacks can also act as a diversion for the target company’s IT and security teams, acting as a smokescreen for other malicious activities. While the incident response team is focused on restoring the attacked server’s performance, hackers might exploit the distraction to carry out phishing attempts or other attacks on sensitive information stored on the server.How to Prevent TCP DDoS AttacksWhen an attack succeeds, it’s already too late to prevent it. Therefore, the best tactics against all kinds of DDoS attacks are defensive measures.One option is to use a comprehensive third-party DDoS mitigation service, like Gcore DDoS Protection, and leave it to the specialists. We recommend this approach, as using a robust, proven protection service is usually the most convenient and effective strategy.Alternatively, you can attempt to apply prevention mechanisms yourself. For TCP DDoS attacks, these include the following:SYN cookies: Protect against SYN flood attacks by adding a special value to SYN-ACK packets. The server will only restore the connection if this value is returned in the client’s ACK message, preventing half-open connections from consuming resources.Filtering and blocking: Identify and block traffic from irrelevant sources or patterns that seem suspicious.Blocking unused ports: Reduce the potential attack surface by closing ports that aren’t in use.Rate limiting: To prevent overload, set thresholds for the amount of traffic the server can handle, including the number of SYN requests.Load balancing and redundancy: Distribute traffic using load balancers and have backup servers ready to handle increased traffic volumes.Caching and CDNs: Use caching and content delivery networks to minimize the resources needed to handle repetitive requests.However, following best security practices doesn’t eliminate the risk of an attack entirely, so it’s also important to monitor traffic for spikes and analyze such spikes for anomalies in order to react promptly in case of an attack. If you’re undertaking DDoS mitigation yourself, this will involve some manual processes. Third-party providers will analyze traffic on your behalf, and some—like Gcore—offer real-time visibility into traffic so you can watch DDoS attacks being stopped as they happen.Thwart Attackers with Gcore DDoS ProtectionOur global network of scrubbing centers is engineered to keep your business operational during a DDoS attack. Your customers will experience uninterrupted functionality even during a DDoS attack, no matter the type. Gcore scrubbing centers are equipped with backup copies of critical systems and network equipment, underscoring our dedication to providing continuous service and robust security.Gcore DDoS Protection offers businesses the following benefits:Robust infrastructure: With over 148 Tbps of network capacity and a global network that’s constantly learning from millions of internet properties, Gcore protects you against the largest and most sophisticated attacks.Proprietary DDoS protection solution: Tailored specifically to ward off a broad spectrum of DDoS threats.Detection of low-frequency attacks from the first query: Even the most subtle attacks are detected.Exceptionally low false-positive rate (less than 0.01%): Maintains normal operations by accurately distinguishing between legitimate traffic and attack vectors.Real-time statistics in the control panel: Offers immediate insights into traffic patterns and potential threats, allowing for swift action.Server protection in your data center: Extends Gcore’s protective measures directly to your infrastructure through a Generic Routing Encapsulation (GRE) tunneling protocol, regardless of location.24/7, highly qualified technical support: Ensures that expert help is always on hand, day or night, to address any concerns or attacks.Exceptional uptime rate with 99.99% SLA: A seamless and uninterrupted user experience backed up by Tier III and IV data centers.ConclusionDDoS attacks, including various kinds of TCP attacks, are still a real threat to online services and can cause real damage to businesses. Preparing for the attacks in advance, however, can help to mitigate their consequences or avoid losses completely.Experience the peace of mind that comes with advanced protection with Gcore DDoS Protection for comprehensive security against DDoS attacks. With over 1 Tbps of total filtering capacity and a 99.99% SLA, your digital assets remain protected from even the most complex, sophisticated, and sustained attacks. Gcore helps to maintain the continuity of your online services, regardless of potential attackers’ motivations.Explore Gcore DDoS Protection

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