XSS in Benjaminjonard Koillection
CVE-2026-110101
Koillection through 1.8.4 contains a stored cross-site scripting vulnerability that allows authenticated users to upload HTML files as Datum file attachments lacking MIME restrictions. Attackers can upload HTML payloads via POST /api/data/{id}/file, served as text/html from public/uploads, executing JavaScript in victims' sessions to perform actions on their behalf.
Vulnerability class: XSS (Cross-Site Scripting)
Published .
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
- github.com/benjaminjonard/koillection/issues/1609 (issue-tracking, technical-description)
- github.com/benjaminjonard/koillection/blob/1.8.4/src/Service/ImageHandler.php (technical-description)
- github.com/benjaminjonard/koillection/blob/1.8.4/src/Entity/Datum.php (technical-description)
- github.com/benjaminjonard/koillection/releases/tag/1.8.4 (release-notes)
- www.vulncheck.com/advisories/koillection-through-1.8.4-stored-xss-via-datum-fil… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-110101?
- CVE-2026-110101 is a medium-severity vulnerability in Benjaminjonard Koillection, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-10-13.
- How severe is CVE-2026-110101?
- Medium severity. CVSS v3 base score is 5.4 out of 10.