Refresh Token Replay Vulnerability in XenForo by XenForo Limited
CVE-2026-73312

9.1CRITICAL

Key Information:

Vendor

Xen Projectforo

Status
Xen Projectforo
Vendor
CVE Published:
8 September 2026

What is CVE-2026-73312?

XenForo prior to version 2.3.13 is susceptible to a refresh token replay vulnerability. This issue arises from the improper handling of refresh tokens, allowing attackers to reuse them even after the associated access token has expired. By exploiting this flaw, attackers can repeatedly submit the same refresh token, enabling them to generate new, independent token pairs and gain unauthorized access for the duration of the token's validity. This vulnerability highlights the importance of securely managing token lifecycle and consumption.

Affected Version(s)

XenForo 0 < 2.3.13

References

https://xenforo.com/community/threads/security-fixes-rele...
vendor-advisorypatch
https://xenforo.com/community/threads/xenforo-2-3-13-and-...
release-notes
https://www.vulncheck.com/advisories/xenforo-refresh-toke...
third-party-advisory

CVSS V4

Score:
9.1
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Marco Paciaroni (BomboBombone)
VulnCheck
.