CVE-2026-23903

Authentication Bypass by Alternate Name vulnerability in Apache Shiro. This issue affects Apache Shiro: before 2.0.7. Users are recommended to upgrade to version 2.0.7, which fixes the issue. The issue only effects static files. If static files are served from a case-insensitive filesystem, such as default macOS setup, static files may be accessed by varying the case of the filename in the request. If only lower-case (common default) filters are present in Shiro, they may be bypassed this way. Shiro 2.1.0 and later has a new parameters to remediate this issue shiro.ini: filterChainResolver.caseInsensitive = true application.properties: shiro.caseInsensitive=true Shiro 3.0.0 and later makes this the default in shiro.ini-based configurations. Shiro 3.0.1 and later makes this the default in all configurations, including programmatic and Spring / Spring Boot.

  • Published Feb 9, 2026
  • CVSS 5.3 medium
  • 0.4% chance of exploitation in the next 30 days (EPSS)
  • A fix is available

Affected software

In the news

CVE-2026-23903 at the National Vulnerability Database