CVE-2026-27166

Discourse is an open source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1 and 2026.1.2, insufficient cleanup in the default Codepen allowed iframes value allows an attacker to trick a user into changing the URL of the main page. This issue has been fixed in versions 2026.3.0-latest.1, 2026.2.1 and 2026.1.2. To workaround this issue, remove Codepen from the list of allowed iframes.

CVSS v3 4.1 MEDIUM

4.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/discourse/discourse/commit/c4762a4fac2f61f52f325396b11d3aeb955ea925	Patch
https://github.com/discourse/discourse/security/advisories/GHSA-h653-cq78-vjj2	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:2026.3.0::::latest:::

History

No history.

Information

Published : 2026-03-19 21:17

Updated : 2026-03-25 01:06

NVD link : CVE-2026-27166

Mitre link : CVE-2026-27166

CVE.ORG link : CVE-2026-27166

JSON object : View

Products Affected

discourse

discourse

CWE

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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