CVE-2026-20912: Gitea: Cross-Repository Authorization Bypass via Release Attachment Linking Leads to Private Attachment Disclosure

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-01-22 · updated 2026-07-15
Weakness: CWE-284

Description

Gitea does not properly validate repository ownership when linking attachments to releases. An attachment uploaded to a private repository could potentially be linked to a release in a different public repository, making it accessible to unauthorized users.

Affected products

Gitea Open Source Git Server: before 1.25.4 — fixed in 1.25.4

How to fix

Upgrade to a fixed version: Gitea Open Source Git Server 1.25.4. Check the vendor advisory for mitigations.

References

https://blog.gitea.com/release-of-1.25.4/
https://github.com/go-gitea/gitea/pull/36320
https://github.com/go-gitea/gitea/pull/36355
https://github.com/go-gitea/gitea/releases/tag/v1.25.4
https://github.com/go-gitea/gitea/security/advisories/GHSA-vfmv-f93v-37mw
https://access.redhat.com/security/cve/CVE-2026-20912
https://bugzilla.redhat.com/show_bug.cgi?id=2432219
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-20912.json

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