CVE-2026-55424

Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a topic "featured link" was not sufficiently normalized and escaped before being rendered in the topic list, allowing a user who can set a featured link to inject JavaScript when default Content Security Policy protections were modified or disabled. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/1bce8881e4253d9bbab56f011a12ef899b926b59	Patch
https://github.com/discourse/discourse/commit/6679d9a5083488bae10c2adbb345c481c583242c	Patch
https://github.com/discourse/discourse/commit/6828aee9b15c2655d63b515ac919830bd540ff83	Patch
https://github.com/discourse/discourse/commit/c9b9405f5bd0bf0269e505e28e3aad388d7657c5	Patch
https://github.com/discourse/discourse/releases/tag/v2026.1.5	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.4.2	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.5.1	Release Notes
https://github.com/discourse/discourse/releases/tag/v2026.6.0	Release Notes
https://github.com/discourse/discourse/security/advisories/GHSA-695w-7fv8-mxg3	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse::::::::
	cpe:2.3:a:discourse:discourse:2026.6.0::::latest:::

History

No history.

Information

Published : 2026-07-09 22:17

Updated : 2026-07-14 01:26

NVD link : CVE-2026-55424

Mitre link : CVE-2026-55424

CVE.ORG link : CVE-2026-55424

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-79

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

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