CVE-2026-56091: Apache Shiro shiro-guice module vulnerable to authentication bypass

June 25, 2026 (updated November 3, 2026)

When using Apache Shiro with the shiro-guice module in a web servlet context, a specially crafted HTTP request may cause an authentication bypass. This vulnerability is similar to https://www.cve.org/CVERecord?id=CVE-2020-1957, except that it affects the shiro-guice module instead of the shiro-spring module.

This issue affects all Apache Shiro versions through 2.x, and 3.0.0-alpha-1 only when using shiro-guice module in a web servlet context.

Upgrade to version 3.0.0 or later, which fixes the issue.

References

Code Behaviors & Features

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