Remote Code Execution in Apache Struts Expression Language Parser
A remote code execution vulnerability exists in Apache Struts 2.5.0 through 2.5.30 due to improper validation of user-supplied OGNL expressions in the expression language parser. An unauthenticated attacker can execute arbitrary code on affected systems by submitting specially crafted expressions.
This section explains the vulnerability in everyday language, so anyone can understand the risk and impact.
There is a serious security flaw in Apache Struts, which is software used to build web applications. The vulnerability allows attackers to take complete control of servers running the affected versions of Struts without needing any password or login credentials.
The problem occurs because Struts doesn't properly check certain types of commands that users can send to the application. An attacker can craft special commands that trick the system into running malicious code. This is particularly dangerous because it can be exploited over the internet without needing any special access to the system.
This vulnerability affects many business applications since Apache Struts is widely used in enterprise environments, especially in financial services and government sectors.
Affected Products
Remediation
1. Upgrade Apache Struts to version 2.5.31 or later
2. If immediate upgrade is not possible, implement WAF rules to block OGNL expressions in request parameters
3. Consider implementing additional input validation at the application level
4. Monitor systems for suspicious OGNL expression patterns