CVE-2026-47733
Rocket.Chat is an open-source, secure, fully customizable communications platform. Prior to 8.5.0, the ImageElement component in packages/gazzodown renders user-controlled src values directly into <a href> and <img src> attributes without protocol sanitization. Unlike the analogous LinkSpan component — which uses sanitizeUrl to block javascript:, data:, and vbscript: protocols — ImageElement passes the raw URL through unchanged. An authenticated user can post a markdown image with a javascript: URL that, if clicked on an older browser, would execute arbitrary JavaScript in the viewer's session. This vulnerability is fixed in 8.5.0.
- CVSS 3.1
- 4.4
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - EPSS
- 0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-25)
- CWE
- CWE-79
- Published
- Modified
- Record from
- the NVD, synced