Vulnerability in Xenforo
CVE-2026-73312
XenForo before 2.3.13 contains a refresh token replay vulnerability that allows attackers to reuse a refresh token multiple times by exploiting the failure to mark tokens as consumed when the parent access token has expired. Attackers can repeatedly submit the same refresh token to generate additional independent token pairs, achieving persistent unauthorized access for the token's full lifetime.
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- disclosure@vulncheck.com (vendor-advisory, patch)
- disclosure@vulncheck.com (release-notes)
- disclosure@vulncheck.com (third-party-advisory)
- disclosure@vulncheck.com (technical-description)
- disclosure@vulncheck.com (exploit)
Frequently asked questions
- What is CVE-2026-73312?
- CVE-2026-73312 is a high-severity vulnerability in Xenforo, classified under Authentication Bypass by Capture-replay. CVSS score: 7.4/10. Published 2026-09-08.
- How severe is CVE-2026-73312?
- High severity. CVSS v3 base score is 7.4 out of 10.
- Is CVE-2026-73312 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.