Gitea exposes private repository diffs to public-only tokens
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-863.
Summary
Gitea through 1.27.2 has an incorrect authorization flaw (CWE-863) in its shared comparison helper, which omits the token repository-access check used when updating pull requests. A token limited to public repositories with read:repository scope can route a comparison or pull request creation through a public base repository and retrieve commit history and diffs from a private head repository the token owner can access. The attacker needs a valid token with read:repository scope, and the flaw bypasses only the public-only token restriction, not the account's underlying repository permissions.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
Gitea's shared comparison helper omits the token repository-access check used when updating pull requests. A public-only token with read:repository scope can route a comparison or pull request creation through a public base repository and retrieve commit history and diffs from a private head repository accessible to the token owner. This bypasses the token's public-only restriction; it does not remove the account's underlying repository permission checks.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- 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-2026-70406
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