Answer in brief
CVE-2026-16889 records a Medium severity (CVSS 4.8) vulnerability in Stored XSS via Pre-Login Notice Image Upload Serves Attacker HTML from Application Origin. The current sources do not mark it as known exploited. The current feed maps Apereo Foundation/openEQUELLA (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 4.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Apereo Foundation/openEQUELLA (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Apereo Foundation/openEQUELLAgeneric | >=2019.1 <2026.1 | 2026.1 |
Published upstream
Oct 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 29, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 29, 2026
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.
Quoted source text, attributed separately from HOL analysis.