CVE-2026-73313 (GCVE-0-2026-73313)
Vulnerability from cvelistv5 – Published: 2026-09-08 13:17 – Updated: 2026-10-01 15:20
VLAI
EPSS
VEX
Title
XenForo < 2.3.13 MFA Bypass via Passkey TFA Provider
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-14 19:22 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
5 references
| URL | Tags |
|---|---|
| https://xenforo.com/community/threads/security-fi… | vendor-advisorypatch |
| https://xenforo.com/community/threads/xenforo-2-3… | release-notes |
| https://bombobombone.github.io/posts/cve-2026-73313/ | technical-description |
| https://github.com/BomboBombone/CVE-2026-73313 | exploit |
| https://www.vulncheck.com/advisories/xenforo-mfa-… | third-party-advisory |
Impacted products
Date Public
2026-09-07 00:00
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