CVE-2025-54656: Apache Struts Extras: Improper Output Neutralization for Logs

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-30 · updated 2026-06-17
Weakness: CWE-117

Description

** UNSUPPORTED WHEN ASSIGNED ** Improper Output Neutralization for Logs vulnerability in Apache Struts. This issue affects Apache Struts Extras: before 2. When using LookupDispatchAction, in some cases, Struts may print untrusted input to the logs without any filtering. Specially-crafted input may lead to log output where part of the message masquerades as a separate log line, confusing consumers of the logs (either human or automated). As this project is retired, we do not plan to release a version that fixes this issue. Users are recommended to find an alternative or restrict access to the instance to trusted users. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.

Affected products

Apache Software Foundation Apache Struts Extras: before 2.0 — fixed in 2.0

How to fix

Upgrade to a fixed version: Apache Software Foundation Apache Struts Extras 2.0. Check the vendor advisory for mitigations.

References

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