Authentication Bypass in Apache Shiro with shiro-guice Module
CVE-2026-56091

8.2HIGH

Key Information:

Vendor

Apache
Status
Apache Shiro
Vendor
CVE Published:
25 June 2026

What is CVE-2026-56091?

An authentication bypass vulnerability exists in Apache Shiro when utilizing the shiro-guice module in a web servlet context. A specially crafted HTTP request can exploit this weakness, leading to unauthorized access. This issue affects all versions of Apache Shiro up through 2.x, as well as version 3.0.0-alpha-1 when the shiro-guice module is deployed within a web servlet context. To mitigate this vulnerability, users are advised to upgrade to version 3.0.0 or later, where the issue has been resolved.

Affected Version(s)

Apache Shiro 0 <= 2.99.99

Apache Shiro 3.0.0-alpha-0 <= 3.0.0-alpha-1

References

https://lists.apache.org/thread/onmtxmy2qonbpx7xlw3o34x8s...
vendor-advisory

CVSS V4

Score:
8.2
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

LocalHost <localhost.detect@gmail.com>
Lenny Primak <lenny@flowlogix.com>
.