Summary
Broken Access Control Vulnerability in Apache Struts2
Who should read this |
All Struts 2 developers and users |
|---|---|
Impact of vulnerability |
Permissions, Privileges, and Access Controls |
Maximum security rating |
Important |
Recommendation |
Developers should immediately upgrade to Struts 2.3.15.3 |
Affected Software |
Struts 2.0.0 - Struts 2.3.15.2 |
Reporter |
Zhu Gang, Zhang Jin, Huawei PSIRT |
CVE Identifier |
Problem
The Struts 2 action mapping mechanism supports the special parameter prefix action: which is intended to help with attaching navigational information to buttons within forms.
In Struts 2 before 2.3.15.3, under certain conditions this can be used to bypass security constraints. More details will available later on when the patch will be widely adopted.
Solution
In Struts 2.3.15.3 the action mapping mechanism was changed to avoid circumventing security constraints. Two additional constants were introduced to steer behaviour of DefaultActionMapper:
- struts.mapper.action.prefix.enabled - when set to false support for "action:" prefix is disabled, set to false by default
- struts.mapper.action.prefix.crossNamespaces - when set to false, actions defined with "action:" prefix must be in the same namespace as current action
Backward Compatibility
After upgrading to Struts 2.3.15.3, applications using the "action:" will stop working. You can use above constants to steer that behaviour.
It is strongly recommended to upgrade to Struts 2.3.15.3, which contains the corrected Struts2-Core library.