Answer in brief
CVE-2026-91122 records a High severity (CVSS 8.7) vulnerability in Discourse: Chat MessageBus delivers read-restricted messages to unauthorized users. The current sources do not mark it as known exploited. The current feed maps discourse/discourse (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 8.7. 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 discourse/discourse (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| discourse/discoursegeneric | <2026.8.0 || >=2026.7.0-latest <2026.7.2 || >=2026.6.0-latest <2026.6.3 || >=2026.1.0-latest <2026.1.8 | 2026.8.0, 2026.7.2, 2026.6.3, 2026.1.8 |
Published upstream
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 25, 2026
Discourse is an open-source discussion platform. Prior to 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0, the video placeholder component allowed crafted HTML to cause an attribute breakout and inject an attacker-controlled event handler. An authenticated user with default trust-level posting privileges could store the crafted placeholder in a post. When another user opened the post and clicked the video play overlay, the handler could execute arbitrary JavaScript in the viewer's session. Default Content Security Policy settings block inline event handlers, but instances with CSP disabled or relaxed could allow the script to read page content and make authenticated requests as the viewer. This issue is fixed in versions 2026.1.8, 2026.6.3, 2026.7.2, and 2026.8.0.
Quoted source text, attributed separately from HOL analysis.