XSS in phpBB

CVE-2026-87901

Improper sanitization in the registration module allows reflected Cross-Site Scripting.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-23 · last modified 2026-10-23.

CVSS v3 metric

CVSS v3 base score 8.3 (High). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

phpBB

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

www.phpbb.com/community/viewtopic.php

Frequently asked questions

What is CVE-2026-87901?: CVE-2026-87901 is a high-severity vulnerability in phpBB, classified under Cross-site Scripting. CVSS score: 8.3/10. Published 2026-10-23.
How severe is CVE-2026-87901?: High severity. CVSS v3 base score is 8.3 out of 10.