Gitea: Cached Per-Branch Permission Check in Pre-Receive Hook Allows Full Repository Write

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

8.8 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS

• CVE-2026-27775: 0.91% estimated exploitation activity in the next 30 days; percentile 59.97 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Vulnerability Header | Field | Value | | ------------------- | ----------------------------------------------------------------------------------- | | Vulnerability Title | Cached Per-Branch Permission Check in Pre-Receive Hook Allows Full Repository Write | | Severity Rating | High | | Bug Category | Authorization Bypass | | Location | routers/private/hookprereceive.go:55-64, CanWriteCode() | | Affected Versions | 1.25.5 | Executive Summary The pre-receive hook in Gitea evaluates the CanMaintainerWriteToBranch permission only once per git push session and caches the result for all subsequent refs in the same batch. An attacker who has a legitimate per-branch write grant (e.g., via an open pull request with "Allow edits from maintainers" enabled) can batch-push that branch together with any other ref. The cached true from the first ref is reused for all following refs, allowing the attacker to overwrite protected branches (including main), create arbitrary new branches, and push…

Published by the source

21 Jul 2026, 21:43 UTC

Last modified by the source

21 Jul 2026, 21:43 UTC

Source last checked

26 Oct 2026, 15:27 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-649p-mmhf-85c7

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# Patch Next advisory brief: CVE-2026-27775

Advisory: Gitea: Cached Per-Branch Permission Check in Pre-Receive Hook Allows Full Repository Write
IDs: CVE-2026-27775, GHSA-649p-mmhf-85c7
Record: https://patchnext.com/advisories/cve-2026-27775 (revision 1, source checked 26 Oct 2026, 15:27 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: code.gitea.io/gitea 1.26.3. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go code.gitea.io/gitea: affected < 1.26.3; fixed in 1.26.3

## Suggested inspection (read-only)
- Go code.gitea.io/gitea: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on code.gitea.io/gitea.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-649p-mmhf-85c7 (GitHub-reviewed advisory GHSA-649p-mmhf-85c7 lists affected ranges: Go code.gitea.io/gitea >=0 <1.26.3)

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