Body-parser 1.20.3 Vulnerability: Details And Fix

by Alex Johnson 50 views

This article addresses a critical security vulnerability found in body-parser-1.20.3.tgz, a Node.js body parsing middleware, with a severity rating of 5.8. We will delve into the details of the vulnerability, its potential impact, and the recommended steps for remediation. This comprehensive guide aims to provide developers and system administrators with the necessary information to mitigate the risk and ensure the security of their applications.

Vulnerable Library: body-parser-1.20.3.tgz

The vulnerability resides in the body-parser library, specifically version 1.20.3. Body-parser is a crucial piece of middleware for Node.js applications, responsible for parsing incoming request bodies before they are handled by your routes. It handles various content types, such as JSON, URL-encoded data, and more, making it a fundamental component in many web applications.

This vulnerability was detected in the HEAD commit of the repository, indicating it is a recent issue that needs prompt attention. The presence of this vulnerability in the body-parser library poses a significant risk, potentially affecting the availability and stability of applications that depend on it. Therefore, understanding the specifics of the vulnerability and the steps to mitigate it are crucial for maintaining application security.

Details of the Vulnerability (CVE-2025-13466)

The specific vulnerability identified is CVE-2025-13466, a medium-severity issue with a CVSS score of 5.8. This vulnerability is a denial-of-service (DoS) attack vector that affects body-parser versions up to 2.2.0. The core of the problem lies in the inefficient handling of URL-encoded bodies containing a large number of parameters. An attacker can exploit this by sending payloads with thousands of parameters within the default 100KB request size limit.

This seemingly innocuous action can have severe consequences. The body-parser middleware, when faced with such a payload, consumes excessive CPU and memory resources while attempting to parse the data. This resource exhaustion can lead to a service slowdown or, in more severe cases, a partial outage. The vulnerability is particularly concerning because it does not require any special privileges or user interaction to exploit, making it easier for attackers to launch DoS attacks.

The impact of this vulnerability is further exacerbated by the fact that it can be triggered within the default request size limit. This means that standard security measures, such as request size limits, may not be sufficient to prevent exploitation. The sustained malicious traffic targeting this vulnerability can lead to significant performance degradation, affecting the user experience and potentially disrupting critical services. Addressing this vulnerability is, therefore, essential to ensure the reliability and availability of applications that rely on body-parser.

Vulnerability Breakdown:

  • CVE ID: CVE-2025-13466
  • Severity: Medium
  • CVSS Score: 5.8
  • Affected Versions: body-parser versions up to 2.2.0
  • Vulnerability Type: Denial of Service (DoS)
  • Description: Inefficient handling of URL-encoded bodies with a large number of parameters.
  • Attack Vector: An attacker sends payloads containing thousands of parameters within the default 100KB request size limit.
  • Impact: Elevated CPU and memory usage, service slowdown, or partial outages.

Dependency Hierarchy:

  • :x: body-parser-1.20.3.tgz (Vulnerable Library)

This hierarchy clearly indicates that the vulnerability stems directly from the body-parser library, making it a direct dependency that needs to be addressed.

Found in:

The vulnerability's presence in the main branch highlights the importance of applying the fix to the primary codebase to prevent potential issues in the production environment.

Threat Assessment

Understanding the threat posed by a vulnerability involves assessing its exploitability and potential impact. For CVE-2025-13466, the following factors contribute to the overall threat assessment:

  • Exploit Maturity: Not Defined
  • EPSS Score: N/A (This likely means the Exploit Prediction Scoring System score is not yet available or applicable at the time of the report.)

The lack of a defined exploit maturity suggests that there may not be readily available exploit code, but it does not diminish the risk. An attacker could still develop an exploit, especially given the clear description of the vulnerability. The absence of an EPSS score further underscores the need for proactive mitigation, as the likelihood of exploitation is uncertain.

Given the medium severity and the potential for DoS attacks, organizations should treat this vulnerability with high priority. The ease with which an attacker can trigger the vulnerability, combined with the potential for significant disruption, makes it a critical issue to address. Ignoring this vulnerability could leave applications vulnerable to resource exhaustion and service interruptions.

CVSS 3 Score Details (5.8)

The Common Vulnerability Scoring System (CVSS) provides a standardized way to assess the severity of vulnerabilities. For CVE-2025-13466, the CVSS 3 score is 5.8, categorized as medium severity. Understanding the components of this score can provide deeper insight into the vulnerability's characteristics.

Base Score Metrics:

The base score is derived from metrics that represent the intrinsic characteristics of the vulnerability:

  • Exploitability Metrics: These metrics reflect the ease with which the vulnerability can be exploited.
    • Attack Vector (AV): Network (N). This indicates that the vulnerability can be exploited remotely over a network, increasing its accessibility to potential attackers.
    • Attack Complexity (AC): Low (L). This means that the conditions required to exploit the vulnerability are minimal, making it easier for an attacker to succeed.
    • Privileges Required (PR): None (N). No privileges are required to exploit the vulnerability, meaning any attacker can attempt to trigger it.
    • User Interaction (UI): None (N). No user interaction is required, allowing the attacker to launch the attack without any involvement from legitimate users.
    • Scope (S): Changed (C). This indicates that an exploitation of the vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component.
  • Impact Metrics: These metrics reflect the potential impact of a successful exploit.
    • Confidentiality Impact (C): None (N). The vulnerability does not lead to any compromise of confidentiality.
    • Integrity Impact (I): None (N). The vulnerability does not lead to any compromise of data integrity.
    • Availability Impact (A): Low (L). The vulnerability can lead to a partial loss of service availability, such as slowdowns or temporary outages.

For more detailed information on CVSS3 Scores, refer to the FIRST CVSS Calculator.

The CVSS score of 5.8, combined with the metric details, paints a clear picture of a vulnerability that is easily exploitable over a network, requires no privileges or user interaction, and can lead to a disruption of service. This underscores the importance of promptly applying the recommended fix.

Suggested Fix

The recommended solution to address CVE-2025-13466 is to upgrade the body-parser library to version 2.2.1 or later. This version contains a fix for the inefficient handling of URL-encoded bodies, resolving the DoS vulnerability.

Steps to Upgrade:

  1. Navigate to your project directory.

  2. Run the following command to update body-parser:

    npm install body-parser@2.2.1

    or

    yarn add body-parser@2.2.1

  3. Verify the updated version in your package.json file.

  4. Test your application thoroughly to ensure compatibility and that the vulnerability is resolved.

Upgrading to version 2.2.1 or later will mitigate the risk posed by CVE-2025-13466 and prevent potential DoS attacks stemming from the inefficient handling of URL-encoded bodies. It is crucial to apply this fix promptly to protect your applications from exploitation.

Automatic Remediation

For organizations looking to streamline their vulnerability remediation process, automatic remediation tools can be highly beneficial. These tools can automatically create pull requests to update vulnerable dependencies, reducing the manual effort required to address security issues.

To enable automatic remediation for this issue, create workflow rules within your Mend (formerly WhiteSource) or similar security platform.

By setting up these rules, you can ensure that vulnerabilities like CVE-2025-13466 are addressed quickly and efficiently, minimizing the risk to your applications. Automatic remediation not only saves time but also helps maintain a strong security posture by ensuring dependencies are always up-to-date with the latest security patches.

Conclusion

The medium-severity vulnerability CVE-2025-13466 in body-parser-1.20.3.tgz poses a real threat to Node.js applications. The potential for denial-of-service attacks due to inefficient handling of URL-encoded bodies makes it crucial to address this issue promptly. By upgrading to body-parser version 2.2.1 or later, you can effectively mitigate this risk and protect your applications from exploitation.

Remember, proactive security measures are essential in today's threat landscape. Regularly monitoring your dependencies for vulnerabilities and applying patches and updates promptly are vital steps in maintaining a secure and resilient application environment. Consider leveraging automatic remediation tools to further streamline your vulnerability management process.

For more information on Node.js security best practices, visit the Node.js Security Working Group. This resource provides valuable insights and guidance on securing your Node.js applications.