CVE-2026-109553

Published: Ott 18, 2026 Last Modified: Ott 19, 2026

ExploitDB:

Other exploit source:

Google Dorks:

HIGH 7,5

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Attack Vector: network

Attack Complexity: high

Privileges Required: low

User Interaction: none

Scope: unchanged

Confidentiality: high

Integrity: high

Availability: high

Description

AI Translation Available

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.