CVE-2026-74239

XenForo before 2.3.13 contains a path traversal vulnerability in the style archive importer on Windows deployments that allows authenticated non-super administrators with style permissions to write arbitrary files outside the intended extraction directory by using backslash-based traversal sequences in ZIP member names. Attackers can craft a malicious ZIP archive with backslash path separators that bypass forward-slash validation to write arbitrary bytes to any web-server-writable path, including the public web root, achieving persistent code execution as the web-server account.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://bombobombone.github.io/posts/cve-2026-74239/	Exploit Third Party Advisory
https://github.com/BomboBombone/CVE-2026-74239	Exploit Third Party Advisory
https://www.vulncheck.com/advisories/xenforo-path-traversal-via-style-archive-importer-on-windows	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 20:30

NVD link : CVE-2026-74239

Mitre link : CVE-2026-74239

CVE.ORG link : CVE-2026-74239

JSON object : View

Products Affected

xenforo

xenforo

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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