Tinyauth: User enumeration attack by timing oracle
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-208.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| tinyauthapp | tinyauth | before 5.1.0 | 5.1.0 | Patch available | CNA |
| — | github.com/tinyauthapp/tinyauth (Go) | before 1.0.1-0.20260714134959-c22925c2fba9 | 1.0.1-0.20260714134959-c22925c2fba9 | Patch available | GHSA-456h-ww26-f758 |
- tinyauth Vendortinyauthapp Affected before 5.1.0 Fixed in 5.1.0 Patch available CNA
- github.com/tinyauthapp/tinyauth (Go) Vendor— Affected before 1.0.1-0.20260714134959-c22925c2fba9 Fixed in 1.0.1-0.20260714134959-c22925c2fba9 Patch available GHSA-456h-ww26-f758
Remediation
- Fix · CNA tinyauth (tinyauthapp) Fixed in 5.1.0
- Fix · GHSA-456h-ww26-f758 github.com/tinyauthapp/tinyauth (Go) Fixed in 1.0.1-0.20260714134959-c22925c2fba9 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-77582
- 2026-10-03 Alias added: GHSA-456h-ww26-f758
- 2026-10-31 EPSS moved to the 50th–90th percentile
- 2026-11-02 EPSS moved to the below the 50th percentile
- 2026-11-03 EPSS moved to the 50th–90th percentile
References
Other 5
- https://github.com/tinyauthapp/tinyauth/security/advisories/GHSA-456h-ww26-f758
- https://github.com/tinyauthapp/tinyauth/pull/1004
- https://github.com/tinyauthapp/tinyauth/commit/c22925c2fba981875d0a2b09dd3ee41c0ae4c310
- https://github.com/tinyauthapp/tinyauth/releases/tag/v5.1.0
- https://github.com/tinyauthapp/tinyauth
More tinyauthapp vulnerabilities
- TI-2026-54080 Tinyauth: Unauthenticated login attempts can trigger global login lockdown denial of service CVSS 3.1MEDIUM 5.3
- TI-2026-54079 Incorrect authorization in tinyauthapp tinyauth CVSS 3.1HIGH 8.1
Sources
- CVE-2026-77582 · CVE Program
- CVE-2026-77582 · NVD
- FIRST EPSS
- GHSA-456h-ww26-f758 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences