Reference page — cumulative record through Sunday, October 4, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-73313

CVE-2026-73313HIGH

XenForo < 2.3.13 MFA Bypass via Passkey TFA Provider

  AV  AC  AT  PR  UI  VC  VI  VA   CVSS    EPSS   %ile   KEV
   N   H   N   L   N   H   H   N    7.6   .0058   45.7     —

AFFECTED
  Product  Versions     Fixed
  XenForo  unspecified  —

TIMELINE
  Aug 11  Reserved by VulnCheck
  Sep 8   Published (CNA: VulnCheck)
  Sep 9   EXPLOIT PUBLISHED — CVE-2026-73313 (XenForo). Public exploit reference added.
  Sep 11  EXPLOIT PUBLISHED — CVE-2026-73313 (XenForo). Public exploit reference added.

CWE-863 · CNA: VulnCheck · CVSS v4.0 · 5 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
August 11, 2026	Reserved	Reserved by VulnCheck
September 8, 2026	Published	Published (CNA: VulnCheck)
September 9, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-73313 (XenForo). Public exploit reference added.
September 11, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-73313 (XenForo). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
XenForo	XenForo	—	—	—

Weaknesses

CWE-863

References (5)

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-bypass-via-passkey-tfa-provider [third-party-advisory]
https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856/ [vendor-advisory, patch]
https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/ [release-notes]

Authoritative record: CVE-2026-73313 at cve.org

Vendors: xenforo

Weaknesses: CWE-863

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-73313 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Sunday, October 4, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.