Analysis Summary

A security upgrade has been made available by the Apache Software Foundation (ASF) to fix a significant flaw in its Tomcat server software that, in some circumstances, may lead to remote code execution (RCE).

According to reports, the vulnerability, which is being tracked as CVE-2024-56337, is an incomplete mitigation for CVE-2024-50379 (CVSS score: 9.8), a major security weakness in the same product that was fixed on December 17, 2024. Depending on the Java version they are using with Tomcat, users who are running Tomcat on a case-insensitive file system with the default servlet write enabled (read-only initialization option set to the non-default value of false) could require further configuration to completely mitigate CVE-2024-50379.

When the default servlet is enabled for writing, these defects are Time-of-check Time-of-use (TOCTOU) race condition vulnerabilities that may cause code execution on case-insensitive file systems. Bypassing Tomcat's case sensitivity checks and treating an uploaded file as a JSP, concurrent reading, and uploading the same file might result in remote code execution.

The revelation coincides with the Zero Day Initiative (ZDI) disclosing information about a serious Webmin vulnerability (CVE-2024-12828, CVSS score: 9.9), enabling arbitrary code execution by authorized remote attackers. The way CGI requests are handled has a specific issue. The problem arises when a user-supplied string is not properly validated before being used to carry out a system call. This flaw allows an attacker to run code in the root context.

Impact

• Code Execution
• Security Bypass

Indicators of Compromise

CVE

• CVE-2024-56337

Affected Vendors

Remediation

• Upgrade to the latest version of Apache Tomcat, available from the Apache Website.
• Organizations must test their assets for the vulnerability mentioned above and apply the available security patch or mitigation steps as soon as possible.
• Implement multi-factor authentication to add an extra layer of security to login processes.
• Regularly monitor network activity for any unusual behavior, as this may indicate that a cyberattack is underway.
• Organizations must stay vigilant and follow best practices for cybersecurity to protect their systems and data from potential threats. This includes regularly updating software and implementing strong access controls and monitoring tools.
• Develop a comprehensive incident response plan to respond effectively in case of a security breach or data leakage.
• Maintain regular backups of critical data and systems to ensure data recovery in case of a security incident.
• Adhere to security best practices, including the principle of least privilege, and ensure that users and applications have only the necessary permissions.
• Establish a robust patch management process to ensure that security patches are evaluated, tested, and applied promptly.
• Conduct security audits and assessments to evaluate the overall security posture of your systems and networks.
• Implement network segmentation to contain and isolate potential threats to limit their impact on critical systems.