CVE-2026-27166

MEDIUM

4.1

Description

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.

CVE Details

CVSS v3.1 Score4.1

SeverityMEDIUM

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredLOW

User InteractionREQUIRED

Published3/19/2026

Last Modified3/25/2026

Sourcenvd

Honeypot Sightings0

Affected Products

discourse:discourse

Weaknesses (CWE)

CWE-80

References

https://github.com/discourse/discourse/commit/c4762a4fac2f61f52f325396b11d3aeb955ea925(security-advisories@github.com)

https://github.com/discourse/discourse/security/advisories/GHSA-h653-cq78-vjj2(security-advisories@github.com)

IOC Correlations

No correlations recorded

This product uses data from the NVD API but is not endorsed or certified by the NVD.