Blind SSRF in Gitea via OpenID assertion verification
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-918 and the CVSS impact.
Summary
When OpenID sign-in is enabled, Gitea processes unauthenticated assertion parameters and sends an HTTP POST request to a caller-supplied OpenID provider endpoint during verification, which is a server-side request forgery (CWE-918). An unauthenticated remote attacker controls the destination and much of the form body, so they can interact with internal HTTP services reachable from the Gitea server. The response is not returned to the attacker, so the impact depends on which services and network addresses the server can reach.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
When OpenID sign-in is enabled, Gitea processes unauthenticated assertion parameters and sends an HTTP POST request to the caller-supplied OpenID provider endpoint during verification. An attacker controls the destination and much of the form body, allowing interaction with internal HTTP services reachable from the Gitea server. The response is not returned to the attacker, so the issue is blind SSRF; its impact depends on the services and network addresses the server can reach.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- 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
Remediation
The sources list no fixed version for Gitea.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Timeline
- 2026-10-14 Threatist record created from CVE-2026-78231
- 2026-10-18 CVSS score added · CISA ADP
- 2026-10-18 CISA SSVC decision points changed
References
More Gitea vulnerabilities
- TI-2026-42785 Gitea before 1.27.1 allows remote code execution via the diffpatch API through Git hook installation. KEVCVSS 3.1CRITICAL 9.8
- TI-2026-42033 Improper authorization on OAuth sign-in callback silently re-enables administrator-disabled accounts CVSS 3.1CRITICAL 9.8
- TI-2026-40842 Privilege Escalation via Access Token Scope Escalation in API CVSS 3.1CRITICAL 9.8
- TI-2026-16922 Gitea Docker image trusts spoofable reverse-proxy headers by default CVSS 3.1CRITICAL 9.8
- TI-2026-42043 Team-repository linking endpoint bypasses the RepoAdminChangeTeamAccess organization setting CVSS 3.1CRITICAL 9.1
- TI-2026-40381 OIDC userinfo Endpoint Returns Identity Claims Without Enforcing API Token Scopes CVSS 3.1CRITICAL 9.1
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences