CVE-2021-31805 : What You Need to Know
Understand CVE-2021-31805, a critical RCE vulnerability in Apache Struts allowing attackers to execute remote malicious code by exploiting forced OGNL evaluation in tag attributes.
A detailed overview of CVE-2021-31805, a vulnerability in Apache Struts that could lead to Remote Code Execution (RCE) due to forced OGNL evaluation in tag attributes.
Understanding CVE-2021-31805
This section provides insights into the nature and impact of the vulnerability.
What is CVE-2021-31805?
CVE-2021-31805 is a security vulnerability present in Apache Struts versions 2.0.0 to 2.5.29. It stems from an incomplete fix issued for a previous CVE, allowing for forced OGNL evaluation on untrusted user input in tag attributes, potentially leading to RCE.
The Impact of CVE-2021-31805
The vulnerability poses a significant risk as attackers can exploit it to execute malicious code remotely, compromising the security and integrity of the affected systems.
Technical Details of CVE-2021-31805
Explore the specific technical aspects and implications of CVE-2021-31805.
Vulnerability Description
The vulnerability arises from the improper handling of forced OGNL evaluation on user input, which, if exploited, can result in RCE, enabling threat actors to take control of the target system.
Affected Systems and Versions
Apache Struts versions 2.0.0 to 2.5.29 are impacted by this vulnerability, leaving systems running these versions exposed to the risk of exploitation.
Exploitation Mechanism
By utilizing the %{...} syntax to force OGNL evaluation on untrusted user input within tag attributes, threat actors can trigger the double evaluation, ultimately leading to RCE.
Mitigation and Prevention
Discover the measures to mitigate the risks associated with CVE-2021-31805 and secure affected systems.
Immediate Steps to Take
To protect your systems, avoid using forced OGNL evaluation on untrusted user input. Consider upgrading to Struts 2.5.30, which includes checks to prevent double evaluation. Refer to Security Bulletin S2-062 for detailed guidance.
Long-Term Security Practices
Implement robust input validation mechanisms, perform regular security audits, and stay informed about the latest Apache Struts security updates to enhance long-term cybersecurity resilience.
Patching and Updates
Stay updated on security patches provided by Apache Struts to address CVE-2021-31805 and other vulnerabilities, ensuring the timely application of patches to safeguard your systems.