Bug 2547093 (CVE-2026-103059)

Summary: CVE-2026-103059 code.gitea.io/gitea: Gitea: Authentication bypass via case-insensitive SSH public key lookup
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: gbenhaim, niyer, twaugh
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Gitea. When the built-in Secure Shell (SSH) server is enabled, public keys are evaluated using a case-insensitive comparison on certain database systems. A remote attacker who constructs a case variant of an existing user's registered public key and possesses the corresponding private key can authenticate as that user over SSH. This flaw allows an attacker to bypass authentication and gain unauthorized access to victim accounts.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-06 19:45:40 UTC 
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.