CVE-2026-59830
Discourse: Stored XSS via unescaped actor name in post actions
CVSS Score
5.4
EPSS Score
0.0%
EPSS Percentile
0th
Discourse is an open-source discussion platform. Prior to 2026.7.0, the post action component failed to escape user-controlled display names before interpolating them into an HTML string passed to trustHTML. A user who could choose a crafted display name could persist markup in post action descriptions. Viewing the affected user activity streams could execute attacker-controlled script in another user's browser. This issue is fixed in version 2026.7.0.
| CWE | CWE-79 |
| Vendor | discourse |
| Product | discourse |
| Published | Sep 21, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
discourse / discourse
< 2026.7.0