CVE-2026-119561

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.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://abraxaslabs.tech/research/PMA-5.2.3-WebAuthn-2FA
https://abraxaslabs.tech/research/phpmyadmin-webauthn
https://github.com/phpmyadmin/phpmyadmin
https://github.com/phpmyadmin/phpmyadmin/blob/RELEASE_5_2_3/libraries/classes/WebAuthn/CustomServer.php#L76-L110
https://www.vulncheck.com/advisories/phpmyadmin-through-5.2.3-webauthn-two-factor-authentication-bypass-via-customserver

Configurations

No configuration.

History

30 Oct 2026, 12:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 12:16

Updated : 2026-10-30 19:14

NVD link : CVE-2026-119561

Mitre link : CVE-2026-119561

CVE.ORG link : CVE-2026-119561

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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