CVE-2011-3923: Code Injection
Apache Struts before 2.3.1.2 allows remote attackers to bypass security protections in the ParameterInterceptor class and execute arbitrary commands.
Other sources
Regular expression in ParametersInterceptor matches top'foo' as a valid expression, which OGNL treats as (top['foo'])(0) and evaluates the value of 'foo' action parameter as an OGNL expression. This lets malicious users put arbitrary OGNL statements into any String variable exposed by an action and have it evaluated as an OGNL expression and since OGNL statement is in HTTP parameter value attacker can use blacklisted characters (e.g. #) to disable method execution and execute arbitrary methods, bypassing the ParametersInterceptor and OGNL library protections.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2011-3923?
CVE-2011-3923 is a vulnerability in Apache Struts before 2.3.1.2 that allows remote attackers to bypass security protections in the ParameterInterceptor.
What is the severity of CVE-2011-3923?
CVE-2011-3923 has a severity level of 9, which is considered critical.
What software is affected by CVE-2011-3923?
CVE-2011-3923 affects Apache Struts versions prior to 2.3.1.2 and Redhat Jboss Enterprise Web Server 1.0.0.
How can I fix CVE-2011-3923?
To fix CVE-2011-3923, update Apache Struts to version 2.3.1.2 or later.
Where can I find more information about CVE-2011-3923?
You can find more information about CVE-2011-3923 [here](https://cwiki.apache.org/confluence/display/WW/S2-009), [here](http://blog.o0o.nu/2012/01/cve-2011-3923-yet-another-struts2.html), and [here](http://seclists.org/fulldisclosure/2014/Jul/38).