This rule aims to detect potential exploitation attempts of OGNL (Object-Graph Navigation Language) injections within JVM-based applications. OGNL is commonly used within various Java frameworks, and the vulnerability arises when user-controlled input is processed as OGNL expressions without appropriate validation. Successful exploitation can lead to Remote Code Execution (RCE), which has been historically evidenced by high-profile vulnerabilities like CVE-2017-5638 and CVE-2022-26134. The rule operates by monitoring application error logs for specific keywords, notably 'org.apache.commons.ognl.OgnlException' and 'ExpressionSyntaxException', which are indicative of OGNL injection attempts. It is crucial that application error logs are properly configured to capture errors at the 'ERROR' logging level or above for this detection to be effective. Overall, this detection rule is essential for safeguarding JVM-based applications from OGNL injection attacks and the serious threats they pose.