CVE-2026-109553Gitea SSH certificate principal impersonation of other users
Updated under an hour ago ()
Does this affect you?
It affects Gitea. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
Gitea resolved the principals of an SSH certificate by searching the content of all stored public keys instead of only principal keys. When Gitea trusts a user certificate authority (`SSH_TRUSTED_USER_CA_KEYS`) and accepts arbitrary principals (`SSH_AUTHORIZED_PRINCIPALS_ALLOW=anything`), a user could register another user's public key line as their own principal, or a holder of a certificate signed by that authority could list it, and then authenticate as the owner of that key through the HTTP signature API and the built-in SSH server. Instances that do not trust a user certificate authority are not affected.
- CVSS
- Not yet scored
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Gitea
- NVD analysis
- Received
- Record last updated
- Oct 18, 2026
- First seen by InfoSec Signals
- Oct 18, 2026
Affected products
Gitea Gitea gitea:gitea (from the name) | through 28.1.0 | CNA record |
References
- https://github.com/go-gitea/gitea/security/advisories/GHSA-vcp6-2qc6-gvq3vendor-advisory
- https://github.com/go-gitea/gitea/pull/39839patch
- https://github.com/go-gitea/gitea/pull/39847patch
- https://blog.gitea.com/release-of-28.2.0/release-notes
- https://github.com/go-gitea/gitea/releases/tag/v28.2.0release-notes
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.