CVE-2026-27166Discourse is an open source discussion platform.
Updated under an hour ago ()
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No exploitation reported and no EPSS estimate yet.
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Free account, 1 product
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
- 5.4 MEDIUM (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
- Weakness (CWE)
- CWE-80
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Analyzed
- Record last updated
- Jun 17, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
discourse discourse discourse:discourse | before 2026.3.0; from 2026.1.0 before 2026.1.2; from 2026.2.0 before 2026.2.1; 2026.3.0 | NVD |
References
- https://github.com/discourse/discourse/commit/c4762a4fac2f61f52f325396b11d3aeb955ea925patch
- https://github.com/discourse/discourse/security/advisories/GHSA-h653-cq78-vjj2vendor-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.