Tinyauth: User enumeration attack by timing oracle

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)

[ Description ]Official description

Tinyauth is an authentication and authorization server. Prior to 5.1.0, Tinyauth exposes a remotely observable timing difference between authentication attempts for existing and nonexistent local usernames. internal/controller/user_controller.go loginHandler and internal/middleware/context_middleware.go basicAuth return quickly after internal/service/auth_service.go reports a missing user, while an existing user causes bcrypt password verification work. Repeated measurements can therefore disclose valid usernames and support targeted credential attacks. This issue is fixed in version 5.1.0.

[ Fixes ]Fixes and patches

• github.com/tinyauthapp/tinyauth 1.0.1-0.20260714134959-c22925c2fba9Fixed version · GitHub Advisories · go package github.com/tinyauthapp/tinyauth: upgrade to 1.0.1-0.20260714134959-c22925c2fba9 or later (affected < 1.0.1-0.20260714134959-c22925c2fba9)

[ Packages ]Affected open-source packages

• github.com/tinyauthapp/tinyauth goAffected < 1.0.1-0.20260714134959-c22925c2fba9 · fixed in 1.0.1-0.20260714134959-c22925c2fba9 · GHSA-456h-ww26-f758

[ References ]References

• github.com/tinyauthapp/tinyauth/security/advisories/GHSA-456h-ww26-f758x_refsource_CONFIRM
• github.com/tinyauthapp/tinyauth/pull/1004x_refsource_MISC
• github.com/tinyauthapp/tinyauth/commit/c22925c2fba981875d0a2b09dd3ee41c0ae4c310x_refsource_MISC
• github.com/tinyauthapp/tinyauth/releases/tag/v5.1.0x_refsource_MISC