Known exploited · Apache
CVE-2018-11776: Apache Struts Remote Code Execution Vulnerability
What it is
Apache Struts contains a vulnerability that allows for remote code execution under two circumstances. One, where the alwaysSelectFullNamespace option is true and the value isn't set for a result defined in underlying configurations and in same time, its upper package configuration have no or wildcard namespace. Or, using URL tag which doesn't have value and action set and in same time, its upper package configuration have no or wildcard namespace.
- Vendor
- Apache
- Product
- Struts
- Added to KEV
- November 3, 2021
- CISA due date
- May 3, 2022
- Ransomware use
- Unknown
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Struts you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before May 3, 2022 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.