phpMyAdmin: Improper Verification of Cryptographic Signature
CVE-2026-119561 is a high-severity improper verification of cryptographic signature vulnerability in phpMyAdmin, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected phpMyAdmin versions: 5.2.3 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of phpMyAdmin you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| phpMyAdmin | phpMyAdmin | 5.2.3 and earlier | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 7.6 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 6.8 | Medium | CNA (vulncheck.com) |
| CVSS 3.1 | 8.1 | High | NVD |
Official description
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- abraxaslabs.tech/research/PMA-5.2.3-WebAuthn-2FAExploit, Mitigation, Third Party Advisory
Technical write-ups (may include proof of concept)
- abraxaslabs.tech/research/phpmyadmin-webauthnExploit, Third Party Advisory
- vulncheck.com/advisories/phpmyadmin-through-5.2.3-webauthn-two-factor-authentication-bypass-via-customserverExploit, Third Party Advisory
Other references
Other vulnerabilities in phpMyAdmin
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
- 9.8 Critical severity
phpMyAdmin Remote Code Execution Exploited
Recent Improper Verification of Cryptographic Signature vulnerabilities
- 8.1 High severity
- 7.5 High severity
- 7.2 High severity
- 7.4 High severity
- 7.4 High severity
- 8.4 High severity
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