In openEQUELLA before 2026.1, the pre-login notice image upload endpoint (PUT /api/preloginnotice/image/{name}) does not validate the type of uploaded files and serves them with a Content-Type derived from the supplied filename. A user holding the EDIT_SYSTEM_SETTINGS permission can upload an HTML file that is then served as text/html from the openEQUELLA origin, resulting in stored cross-site scripting. Unauthenticated exploitation is possible where EDIT_SYSTEM_SETTINGS has been granted to the guest user or everyone.
History

Thu, 29 Oct 2026 03:00:00 +0000

Type Values Removed Values Added
First Time appeared Apereo Foundation
Apereo Foundation openequella
Vendors & Products Apereo Foundation
Apereo Foundation openequella

Thu, 29 Oct 2026 02:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Thu, 29 Oct 2026 01:45:00 +0000

Type Values Removed Values Added
Description In openEQUELLA before 2026.1, the pre-login notice image upload endpoint (PUT /api/preloginnotice/image/{name}) does not validate the type of uploaded files and serves them with a Content-Type derived from the supplied filename. A user holding the EDIT_SYSTEM_SETTINGS permission can upload an HTML file that is then served as text/html from the openEQUELLA origin, resulting in stored cross-site scripting. Unauthenticated exploitation is possible where EDIT_SYSTEM_SETTINGS has been granted to the guest user or everyone.
Title Stored XSS via Pre-Login Notice Image Upload Serves Attacker HTML from Application Origin
Weaknesses CWE-434
References
Metrics cvssV4_0

{'score': 4.8, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: MON-CSIRT

Published: 2026-10-29T01:32:09.466Z

Updated: 2026-10-29T02:02:13.700Z

Reserved: 2026-07-24T05:06:16.448Z

Link: CVE-2026-16889

cve-icon Vulnrichment

Updated: 2026-10-29T01:54:22.052Z

cve-icon NVD

Status : Deferred

Published: 2026-10-29T02:16:51.803

Modified: 2026-10-29T15:56:34.127

Link: CVE-2026-16889

cve-icon Redhat

No data.