VulnerabilityAnalyzed

CVE-2026-35054

XenForo before 2.3.9 is vulnerable to stored cross-site scripting (XSS) related to BB code rendering.

MEDIUM 5.1EPSS 0.14%

Does this matter?

Lower severity and a low EPSS score (0.14%). Track it; it rarely justifies an emergency change on its own.

Description

XenForo before 2.3.9 is vulnerable to stored cross-site scripting (XSS) related to BB code rendering. An attacker can inject malicious scripts through BB code that are stored and executed when other users view the content.

CVSS 4.0: 5.1 MEDIUMCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.14% probability · 4th percentile
CISA KEV: Not listed
Weakness: CWE-79
Affected: xenforo/xenforo
Source: disclosure@vulncheck.com

References

https://www.vulncheck.com/advisories/xenforo-stored-cross-site-scripting-via-bb-code-renderingThird Party Advisory
https://xenforo.com/community/threads/xenforo-2-3-9-inc-xfmg-2-2-18-released-security-fix.235659/Release Notes

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.