Home

Description

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.

PUBLISHED Reserved 2026-04-01 | Published 2026-04-01 | Updated 2026-05-24 | Assigner VulnCheck




MEDIUM: 5.1CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
MEDIUM: 6.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Problem types

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

Product status

2.3.0 (semver) before 2.3.9
affected

Any version before 2.2.18
affected

Credits

UwU finder

References

xenforo.com/...inc-xfmg-2-2-18-released-security-fix.235659/ (XenForo 2.3.9 (inc XFMG) & 2.2.18 Released (Security Fix)) vendor-advisory patch

www.vulncheck.com/...ss-site-scripting-via-lightbox-in-posts (VulnCheck Advisory: XenForo Cross-Site Scripting via Lightbox in Posts) third-party-advisory

cve.org (CVE-2026-35055)

nvd.nist.gov (CVE-2026-35055)

Download JSON