CVE-2026-77560 (GCVE-0-2026-77560)
Vulnerability from cvelistv5
Published
2026-09-21 16:39
Modified
2026-09-21 20:45
CWE
  • CWE-178 - Improper Handling of Case Sensitivity
  • CWE-636 - Not Failing Securely ('Failing Open')
  • CWE-863 - Incorrect Authorization
Summary
Tinyauth is an authentication and authorization server. Prior to 5.1.2, Tinyauth compares forwarded hostnames case-sensitively while reverse proxies route equivalent hostnames case-insensitively, allowing an authenticated low-privilege user to bypass per-app access controls with a differently cased hostname. The lookup in internal/service/access_controls_service.go through lookupStaticACLs and GetAccessControls, and the Docker-label fallback in internal/service/docker_service.go through GetLabels, can miss the configured app and return an empty access-control object. internal/controller/proxy_controller.go proxyHandler then treats the empty user, group, OAuth, LDAP, and IP restrictions as permissive and returns an authenticated result for an app that should exclude the user. Unauthenticated users remain subject to login, and global login-time allowlists are not bypassed. This issue is fixed in version 5.1.2.
Impacted products
Vendor Product Version
tinyauthapp tinyauth Version: < 5.1.2
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Show details on NVD website


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