CVE-2026-73319

XenForo before 2.3.13 contains a cross-site scripting vulnerability in the dynamic redirect handler that allows unauthenticated attackers to execute arbitrary JavaScript in the board origin by crafting a malicious javascript: URI that bypasses host validation. Attackers can embed the board hostname in the URI authority component and use percent-encoded newlines to evade server-side filters, causing authenticated users who perform a Follow action to execute attacker-supplied JavaScript in their browser.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://bombobombone.github.io/posts/cve-2026-73319/	Exploit Third Party Advisory
https://github.com/BomboBombone/CVE-2026-73319	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/xenforo-xss-via-dynamic-redirect-handler	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 20:26

NVD link : CVE-2026-73319

Mitre link : CVE-2026-73319

CVE.ORG link : CVE-2026-73319

JSON object : View

Products Affected

xenforo

xenforo

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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