Bug 2563944 (CVE-2026-119561)

Summary: CVE-2026-119561 phpMyAdmin: phpMyAdmin: Two-factor authentication bypass via unverified WebAuthn signatures
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in phpMyAdmin. This issue allows a remote attacker with valid database credentials to bypass two-factor authentication (2FA). The application fails to verify Web Authentication (WebAuthn) cryptographic assertion signatures against stored public keys during login. An attacker can exploit this flaw by submitting a crafted authentication response, allowing them to bypass secondary authentication and gain unauthorized access to the database.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2565553, 2565555, 2565556, 2565557, 2565558    
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Description OSIDB Bzimport 2026-10-30 11:52:30 UTC 
phpMyAdmin through 5.2.3 contains an authentication bypass vulnerability in CustomServer::parseAndValidateAssertionResponse() that never verifies WebAuthn assertion signatures against stored public keys. Attackers holding a victim's MySQL credentials can POST a crafted webauthn_request_response with matching challenge, origin, and rpIdHash to bypass the second factor and gain database privileges.