What’s Vulnerable › Vulnerabilities

CVE-2026-103059: Gitea built-in SSH server authentication bypass through key case folding

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-06 · updated 2026-10-15
• Weakness: CWE-305

Description

When Gitea's built-in SSH server is enabled (`START_SSH_SERVER = true`), the presented public key was looked up with an SQL `LIKE` comparison of its encoded content, which is case-insensitive on some databases, including the default SQLite. An attacker who can construct a case variant of another user's registered RSA public key for which they can derive the private key could have that key matched to the victim's account and authenticate over SSH as that user. Keys are now looked up by fingerprint.

Affected products

• Gitea Open Source Git Server: before 28.0.0 — fixed in 28.0.0

How to fix

Upgrade to a fixed version: Gitea Open Source Git Server 28.0.0. Check the vendor advisory for mitigations.

References

• https://blog.gitea.com/release-of-28.0.0/
• https://github.com/go-gitea/gitea/pull/39423
• https://github.com/go-gitea/gitea/releases/tag/v28.0.0
• https://github.com/go-gitea/gitea/security/advisories/GHSA-8pwg-hcgm-54cp

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