CVE-2026-73313 XenForo < 2.3.13 MFA Bypass via Passkey TFA Provider

What is CVE-2026-73313?

CVE-2026-73313 is a high-severity authentication bypass vulnerability in XenForo, published on 8 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

Official description

XenForo before 2.3.13 contains a multi-factor authentication bypass vulnerability in the passkey TFA provider that allows an authenticated attacker to complete login as another user by submitting their own registered passkey credential during the WebAuthn assertion step. The passkey verification path performs a global credential lookup without validating that the matched credential belongs to the user whose login is pending, enabling an attacker who knows a target account's password to sign the challenge with their own passkey and bypass multi-factor authentication on both public forum and ACP login paths.

Weakness: CWE-863

Which versions are affected by CVE-2026-73313?

It affects 1 product.

Products include Xenforo Xenforo.

How do I fix CVE-2026-73313?

No fix has been published for CVE-2026-73313 yet. Limit exposure of the affected software until one is available.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-73313 being exploited?

There is no known exploitation of CVE-2026-73313 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

Other vulnerabilities in XenForo

• CVE-2025-71279 XenForo Passkey Security Bypass Critical 9.3
• CVE-2026-73309 XenForo < 2.3.13 Authentication Bypass via OAuth2 Token Endpoint Critical 9.1
• CVE-2026-73311 XenForo < 2.3.13 OAuth2 Authorization Code Reuse Critical 9.1
• CVE-2026-73312 XenForo < 2.3.13 Refresh Token Replay via Expired Access Token Critical 9.1
• CVE-2024-38457 Xenforo before 2.2.16 allows CSRF. High 8.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-wwh4-p7r6-v97f.