Remote Code Execution in Apache Struts 3.0.1 through Expression Language Injection
Apache Struts versions 3.0.1 through 3.0.8 contain a critical vulnerability in the expression language (EL) processor that allows remote attackers to execute arbitrary code via crafted OGNL expressions in HTTP request parameters when dynamic method invocation is enabled.
This section explains the vulnerability in everyday language, so anyone can understand the risk and impact.
This 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 by sending specially crafted web requests.
The problem occurs because Struts doesn't properly check and filter certain types of input that users can send to the application. Attackers can exploit this to run any commands they want on the server, potentially stealing data, installing malware, or taking over the entire system.
This vulnerability is particularly dangerous because it's relatively easy to exploit and can be attacked from anywhere on the internet if the vulnerable application is accessible.
Affected Products
Remediation
1. Upgrade to Apache Struts version 3.0.9 or later immediately
2. If immediate upgrade is not possible, disable dynamic method invocation by setting 'struts.enable.DynamicMethodInvocation=false' in struts.xml
3. Implement WAF rules to block requests containing suspicious OGNL expressions
4. Monitor systems for signs of exploitation