CVE-2026-73310 (GCVE-0-2026-73310)
Vulnerability from cvelistv5 – Published: 2026-09-08 13:16 – Updated: 2026-10-01 15:20
VLAI
EPSS
VEX
Title
XenForo < 2.3.13 OAuth2 Authorization Code Token Theft via redirect_uri Bypass
Summary
XenForo before 2.3.13 contains an authorization flaw in the OAuth2 token endpoint that allows attackers controlling any allowlisted redirect URI to bypass redirect URI binding by submitting a different allowlisted URI than the one recorded at authorization time. Attackers can exchange an intercepted authorization code using a mismatched redirect URI to steal OAuth2 tokens from intercepted authorization flows.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-08 13:44 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-2026-73310/ | technical-description |
| https://github.com/BomboBombone/CVE-2026-73310 | exploit |
| https://www.vulncheck.com/advisories/xenforo-oaut… | third-party-advisory |
Impacted products
Date Public
2026-09-07 00:00
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