What is CVE-2026-35057?

CVE-2026-35057 is a medium-severity vulnerability in Xenforo, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-04-01.

How severe is CVE-2026-35057?

Medium severity. CVSS v3 base score is 6.4 out of 10.

XSS in Xenforo

CVE-2026-35057

XenForo before 2.3.10 and before 2.2.19 is vulnerable to stored cross-site scripting (XSS) in structured text mentions, primarily affecting legacy profile post content. An attacker can inject malicious scripts through crafted mentions that are stored and executed when other users view the content.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (6.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

Affected products

Xenforo — versions 2.3.0, 0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

disclosure@vulncheck.com (vendor-advisory, Release Notes, patch)
disclosure@vulncheck.com (Exploit, Third Party Advisory, exploit)

Frequently asked questions

What is CVE-2026-35057?: CVE-2026-35057 is a medium-severity vulnerability in Xenforo, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-04-01.
How severe is CVE-2026-35057?: Medium severity. CVSS v3 base score is 6.4 out of 10.