Apache Struts Expression Language Injection Remote Code Execution
Severe, but no confirmed exploitation yet. Schedule remediation in your next patch cycle and apply mitigations if you're exposed.
An unauthenticated attacker, remotely over the network, with no user interaction, can fully compromise the system — steal data, tamper with it and take it offline.
Improper neutralization of special elements used in an expression language statement ('Expression Language Injection') vulnerability in Apache Struts. If the application is configured to use the legacy RESTful action mapper, a crafted request can inject an OGNL expression that may lead to remote code execution. Struts 7 is affected only when the OGNL allowlist is disabled; it is enabled by default. Applications using the default action mapper, the restful2 mapper, or the Struts REST plugin are not affected. This issue affects Apache Struts: from 2.0.0 through 2.3.37, from 2.5.0 through 2.5.33, from 6.0.0 through 6.11.0, from 7.0.0 through 7.3.0. Users are recommended to upgrade to version 6.12.0 or 7.4.0, which fixes the issue.
Inferred from the weakness type (CWE) and how the flaw is reached — the techniques an attacker would chain to exploit this. Real-world corroboration appears here as threat intel is folded in.
Generated by Wavense from the CVE record — an immediate mitigation and the permanent fix.
Temporarily, disable or migrate away from the legacy RESTful action mapper if currently in use, as it is a prerequisite for exploitation. For Struts 7, ensure the OGNL allowlist is explicitly enabled, as it significantly reduces the attack surface. Implement robust input validation and web application firewall (WAF) rules to detect and block crafted OGNL injection attempts.
The permanent resolution is to upgrade Apache Struts to a non-vulnerable version. Specifically, upgrade to version 6.12.0 or later for the 6.x branch, or version 7.4.0 or later for the 7.x branch. This addresses the Expression Language Injection vulnerability by properly neutralizing special elements and patching the affected components.
An attacker can exploit this vulnerability by sending a specially crafted request to inject an OGNL expression, particularly when using the legacy RESTful action mapper. This allows for remote code execution on the server, granting full control over the affected system. The consequences include data breaches, service disruption, and potential lateral movement within the network.
Other CVEs affecting struts
Forced OGNL evaluation, when evaluated on raw user input in tag attributes, may lead to remote code execution. Affected software : Apache Struts 2.0.0 - Struts 2.5.25.
The Struts 1 plugin in Apache Struts 2.1.x and 2.3.x might allow remote code execution via a malicious field value passed in a raw message to the ActionMessage.
The Jakarta Multipart parser in Apache Struts 2 2.3.x before 2.3.32 and 2.5.x before 2.5.10.1 has incorrect exception handling and error-message generation during file-upload attempts, which allows remote attackers to execute arbitrary commands via a crafted Content-Type, Content-Disposition, or Content-Length HTTP header, as exploited in the wild in March 2017 with a Content-Type header containing a #cmd= string.
Apache Struts 2.0.0 through 2.3.15 allows remote attackers to execute arbitrary OGNL expressions via a parameter with a crafted (1) action:, (2) redirect:, or (3) redirectAction: prefix.
The ExceptionDelegator component in Apache Struts before 2.2.3.1 interprets parameter values as OGNL expressions during certain exception handling for mismatched data types of properties, which allows remote attackers to execute arbitrary Java code via a crafted parameter.
Apache Struts versions 2.3 to 2.3.34 and 2.5 to 2.5.16 suffer from possible Remote Code Execution when alwaysSelectFullNamespace is true (either by user or a plugin like Convention Plugin) and then: results are used with no namespace and in same time, its upper package have no or wildcard namespace and similar to results, same possibility when using url tag which doesn't have value and action set and in same time, its upper package have no or wildcard namespace.
The REST Plugin in Apache Struts 2.1.1 through 2.3.x before 2.3.34 and 2.5.x before 2.5.13 uses an XStreamHandler with an instance of XStream for deserialization without any type filtering, which can lead to Remote Code Execution when deserializing XML payloads.
ActionForm in Apache Software Foundation (ASF) Struts before 1.2.9 with BeanUtils 1.7 allows remote attackers to cause a denial of service via a multipart/form-data encoded form with a parameter name that references the public getMultipartRequestHandler method, which provides further access to elements in the CommonsMultipartRequestHandler implementation and BeanUtils.