Description
Discourse is an open-source discussion platform. Prior to 2026.1.7, an authenticated user could submit specially formed URLs that bypassed the Onebox allowlist and embedded malicious content in a site. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1.
References2
Metrics
- CVSS 3.1
-
6.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 25 · as of 12 November 2026
- CWE
- CWE-20
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.