CVE-2026-35055

MEDIUM 6.1

XenForo Cross-Site Scripting via Lightbox in Posts

CVSS Score

6.1

EPSS Score

0.0%

EPSS Percentile

8th

XenForo before 2.3.9 and before 2.2.18 is vulnerable to cross-site scripting (XSS) related to lightbox usage in posts. An attacker can inject malicious scripts that execute when users interact with post content displayed in the lightbox.

CWE	CWE-79
Vendor	xenforo
Product	xenforo
Published	Apr 1, 2026
Last Updated	Apr 1, 2026

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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

None

Integrity

None

Availability

None

Affected Versions

XenForo / XenForo

2.3.0 < 2.3.9 0 < 2.2.18

References

NVD ↗ CVE.org ↗ EPSS Data ↗

xenforo.com: https://xenforo.com/community/threads/xenforo-2-3-9-inc-xfmg-2-2-18-released-security-fix.235659/ vulncheck.com: https://www.vulncheck.com/advisories/xenforo-cross-site-scripting-via-lightbox-in-posts

Credits

UwU