XSS in Yeswiki

CVE-2026-104461

YesWiki before 4.6.7 contains a stored cross-site scripting vulnerability in the Bazar FileField, which validates only the upload's file extension and never calls HtmlPurifierService::cleanFile, so SVG files are stored verbatim and served inline as image/svg+xml. Authenticated users can submit entries via POST /api/entries/{formId} with SVG files containing script that executes in the wiki origin when the file is opened, enabling administrator session or account compromise.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

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

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-104461?
CVE-2026-104461 is a medium-severity vulnerability in Yeswiki, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-10-02.
How severe is CVE-2026-104461?
Medium severity. CVSS v3 base score is 5.4 out of 10.