Dashboard / CVE-2026-109553

CVE-2026-109553

HIGH
MEDIUM Priority: 0.01 BB Relevance: 55/100
Published: 2026-10-18 Modified: 2026-11-02 First seen: 2026-11-02 Status: active

Attack Surface

Network No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: High
PR: Low
UI: None
S: Unchanged
C: High
I: High
A: High

Description

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.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
Gitea Gitea 0

References & Advisories (5)

Bug Bounty Relevance

55 / 100
✓ Network accessible
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.18%
Raw Score 0.001750
Percentile 7.0%
Date 2026-11-03

EPSS Trend

2026-11-03
0.00175
2026-11-02
0.00198

Intelligence Sources

mitre ref →
nvd ref →

External Links