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 v3 4.4 MEDIUM

4.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/RocketChat/Rocket.Chat/security/advisories/GHSA-vvrf-fq54-q4pr
https://github.com/RocketChat/Rocket.Chat/security/advisories/GHSA-vvrf-fq54-q4pr

Configurations

No configuration.

History

25 Jun 2026, 16:16

Type	Values Removed	Values Added
References	~~() https://github.com/RocketChat/Rocket.Chat/security/advisories/GHSA-vvrf-fq54-q4pr -~~	() https://github.com/RocketChat/Rocket.Chat/security/advisories/GHSA-vvrf-fq54-q4pr -

24 Jun 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-24 21:16

Updated : 2026-06-25 16:16

NVD link : CVE-2026-47733

Mitre link : CVE-2026-47733

CVE.ORG link : CVE-2026-47733

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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