Description
Discourse is an open-source community discussion platform. Versions 3.5.0 and below are vulnerable to XSS attacks through parsing and rendering of chat channel titles and chat thread titles via the quote message functionality when using the rich text editor. This issue is fixed in version 3.5.1.
Scores
CVSS v3
3.5
EPSS
0.0004
EPSS Percentile
13.6%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-80
Status
published
Products (3)
discourse/discourse
3.6.0 beta1
discourse/discourse
< 3.5.0
discourse/discourse
< 3.6.0
Published
Oct 01, 2025
Tracked Since
Feb 18, 2026