CVE-2026-73310

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bombobombone.github.io/posts/cve-2026-73310/	Exploit Third Party Advisory
https://github.com/BomboBombone/CVE-2026-73310	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/xenforo-oauth2-authorization-code-token-theft-via-redirect-uri-bypass	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/	Release Notes
https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857/	Release Notes

Configurations

Configuration 1 (hide)

cpe:2.3:a:xenforo:xenforo:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-09-08 14:17

Updated : 2026-09-11 20:36

NVD link : CVE-2026-73310

Mitre link : CVE-2026-73310

CVE.ORG link : CVE-2026-73310

JSON object : View

Products Affected

xenforo

xenforo

CWE

CWE-863

Incorrect Authorization

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