EUVD-2024-3542

Comprehensive Technical Analysis of EUVD-2024-3542

1. Vulnerability Assessment and Severity Evaluation

The EUVD-2024-3542 entry describes a Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in Apache Tomcat. This type of vulnerability occurs when the state of a system changes between the time it is checked and the time it is used, leading to potential security issues. The vulnerability affects multiple versions of Apache Tomcat and has a high base score of 9.8 according to the CVSS v3.1 scoring system. This score indicates a critical severity due to the following factors:

• Attack Vector (AV:N): The vulnerability can be exploited over the network.
• Attack Complexity (AC:L): The attack requires low complexity.
• Privileges Required (PR:N): No privileges are required to exploit the vulnerability.
• User Interaction (UI:N): No user interaction is required.
• Scope (S:U): The vulnerability does not change the security scope.
• Confidentiality (C:H): High impact on confidentiality.
• Integrity (I:H): High impact on integrity.
• Availability (A:H): High impact on availability.

2. Potential Attack Vectors and Exploitation Methods

The TOCTOU vulnerability can be exploited by an attacker who can manipulate the state of the system between the time a check is performed and the time the system uses the checked state. Specifically, in the context of Apache Tomcat, this could involve:

• File System Manipulation: An attacker could manipulate files on a case-insensitive file system to bypass security checks.
• Servlet Manipulation: An attacker could exploit the default servlet write functionality to inject malicious code or manipulate data.

3. Affected Systems and Software Versions

The vulnerability affects the following versions of Apache Tomcat:

• Apache Tomcat 11.0.0-M1 through 11.0.1
• Apache Tomcat 10.1.0-M1 through 10.1.33
• Apache Tomcat 9.0.0.M1 through 9.0.97

4. Recommended Mitigation Strategies

To mitigate this vulnerability, the following steps are recommended:

• Update Apache Tomcat: Upgrade to the latest versions of Apache Tomcat that include the necessary fixes:

  • Apache Tomcat 11.0.3 or later
  • Apache Tomcat 10.1.35 or later
  • Apache Tomcat 9.0.99 or later

• Configure Java System Properties: Depending on the version of Java being used, configure the sun.io.useCanonCaches system property:

  • Java 8 or Java 11: Set sun.io.useCanonCaches to false.
  • Java 17: Ensure sun.io.useCanonCaches is set to false if it is set at all.
  • Java 21 onwards: No additional configuration is required as the problematic cache has been removed.

• Disable Default Servlet Write: If possible, disable the default servlet write functionality by setting the readonly initialization parameter to true.

5. Impact on European Cybersecurity Landscape

The vulnerability poses a significant risk to organizations using Apache Tomcat within the European Union. Given the widespread use of Apache Tomcat in web applications, the potential impact includes:

• Data Breaches: Unauthorized access to sensitive data.
• Service Disruption: Potential denial-of-service attacks.
• Compliance Issues: Non-compliance with data protection regulations such as GDPR.

6. Technical Details for Security Professionals

• Vulnerability Identification: The vulnerability is identified by CVE-2024-56337 and GHSA-27hp-xhwr-wr2m.

• References:

  • NVD Detail
  • Apache Tomcat GitHub
  • Apache Security Mailing List
  • NetApp Security Advisory
  • [Apache Tomcat Security Advisories](https://tomcat.apache.org/security-10.html#Fixed_in_Apache_Tomcat_10.1.34, https://tomcat.apache.org/security-11.html#Fixed_in_Apache_Tomcat_11.0.2, https://tomcat.apache.org/security-9.html#Fixed_in_Apache_Tomcat_9.0.98)
  • CVE Record

• EPSS Score: The Exploit Prediction Scoring System (EPSS) score is 4, indicating a moderate likelihood of exploitation.

• ENISA IDs:

  • Product: Apache Tomcat versions 10.1.0-M1 through 10.1.33, 9.0.0.M1 through 9.0.97, and 11.0.0-M1 through 11.0.1.
  • Vendor: Apache Software Foundation.

Conclusion

The TOCTOU Race Condition vulnerability in Apache Tomcat is a critical issue that requires immediate attention. Organizations should prioritize updating their Apache Tomcat installations and configuring the necessary Java system properties to mitigate the risk. The potential impact on the European cybersecurity landscape underscores the importance of prompt action to protect sensitive data and ensure compliance with regulatory requirements.