CVE-2026-110101

EUVD-2026-98934
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.
Cross-site Scripting
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
VulnCheckCNA
5.4 MEDIUM
NETWORK
LOW
LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: 11.08%
Early Detection
Affected products identified ahead of NVD analysis through intelligence sources.
VendorProductVersionSource
benjaminjonardkoillection
𝑥
≤ 1.8.4
CNA
Common Weakness Enumeration
References
https://github.com/benjaminjonard/koillection/blob/1.8.4/src/Entity/Datum.php#L141-L145
https://github.com/benjaminjonard/koillection/blob/1.8.4/src/Service/ImageHandler.php#L43-L50
https://github.com/benjaminjonard/koillection/issues/1609
https://github.com/benjaminjonard/koillection/releases/tag/1.8.4
https://www.vulncheck.com/advisories/koillection-through-1.8.4-stored-xss-via-datum-file-attachment-uploads