Known exploited · Apache
CVE-2016-4437: Apache Shiro Code Execution Vulnerability
What it is
Apache Shiro contains a vulnerability which may allow remote attackers to execute code or bypass intended access restrictions via an unspecified request parameter when a cipher key has not been configured for the "remember me" feature.
- Vendor
- Apache
- Product
- Shiro
- Added to KEV
- November 3, 2021
- CISA due date
- May 3, 2022
- Ransomware use
- Unknown
- Weakness
- CWE-284: Improper Access Control
What CISA requires
Apply updates per vendor instructions.
Forensic triage
No
What to do now
- Find every instance of Shiro 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.