What is CVE-2026-63171?

CVE-2026-63171 is a medium-severity vulnerability in Omnispace Agora Project, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-10-13.

How severe is CVE-2026-63171?

Medium severity. CVSS v3 base score is 5.4 out of 10.

XSS in Omnispace Agora Project

CVE-2026-63171

Omnispace Agora Project before 26.10.0 contains a stored cross-site scripting vulnerability that allows authenticated attackers to inject malicious script by submitting a crafted forum category description containing a double-quote character that breaks out of an HTML input value attribute. Attackers can exploit the HTMLPurifier configuration that preserves double-quotes to escape the attribute context and execute arbitrary script in the browser of users viewing the forum category.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2026-10-13 · last modified 2026-10-14.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

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

Omnispace Agora Project

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/xech/agora-project/releases/tag/26.10 (release-notes, patch)
www.agora-project.net/ (product)
www.vulncheck.com/advisories/omnispace-agora-project-stored-xss-via-category-de… (third-party-advisory)

Frequently asked questions

What is CVE-2026-63171?: CVE-2026-63171 is a medium-severity vulnerability in Omnispace Agora Project, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-10-13.
How severe is CVE-2026-63171?: Medium severity. CVSS v3 base score is 5.4 out of 10.