CVE-2026-16889

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/openequella/openEQUELLA/security/advisories/GHSA-q2xv-rffq-mj5w
https://openequella.github.io/guides/

Configurations

No configuration.

History

29 Oct 2026, 02:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 02:16

Updated : 2026-10-29 15:56

NVD link : CVE-2026-16889

Mitre link : CVE-2026-16889

CVE.ORG link : CVE-2026-16889

JSON object : View

Products Affected

No product.

CWE

CWE-434

Unrestricted Upload of File with Dangerous Type

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