XSS in Qgis
CVE-2026-104140
QGIS is a free, open source, cross-platform geographic information system. Prior to 3.44.12 and 4.0.0 through 4.2.3, QGIS Server renders feature data in WFS3 (OGC API Features) HTML responses without HTML escaping. Attacker-controlled feature.properties values from a published writable vector layer reach resources/server/api/ogc/templates/wfs3/getFeatures.html through QgsServerOgcApiHandler::htmlDump and the if_nullptr_null_str callback. A user who opens an items HTML page can execute stored markup or script in the QGIS Server origin, which can expose the viewer's session data or issue authenticated requests with the viewer's privileges. This issue is fixed in version 3.44.12.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/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
- Qgis — versions < 3.44.12, >= 4.0.0, <= 4.2.3
Weakness classification (CWE)
References
- github.com/qgis/QGIS/security/advisories/GHSA-cr49-pm9v-m788
- github.com/qgis/QGIS/pull/66616
- github.com/qgis/QGIS/pull/67044
- github.com/qgis/QGIS/commit/1930e81c918818a4f5412219f8f7e470d2709f91
- github.com/qgis/QGIS/commit/ca76fcac616dbf1c0446514fd6517296eb7c6904
- github.com/qgis/QGIS/releases/tag/final-3_44_12
Frequently asked questions
- What is CVE-2026-104140?
- CVE-2026-104140 is a medium-severity vulnerability in Qgis, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-10-12.
- How severe is CVE-2026-104140?
- Medium severity. CVSS v3 base score is 6.1 out of 10.