CVE-2026-33395

Severity CVSS v4.0:

Pending analysis

Type:

CWE-79 Cross-Site Scripting (XSS)

Publication date:

19/03/2026

Last modified:

24/03/2026

Description

Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the discourse-graphviz plugin contains a stored cross-site scripting (XSS) vulnerability that allows authenticated users to inject malicious JavaScript code through DOT graph definitions. For instances with CSP disabled only. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, disable the graphviz plugin, upgrade to a patched version, or enable a content security policy.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N CVSS v3.1 Severity and Metrics:

Base Score: 4.40 MEDIUM
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): Low
User Interaction (UI): Required
Scope (S): Changed
Confidentiality (C): Low
Integrity (I): Low
Availability (A): None

Base Score 3.x

4.40

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:a:discourse:discourse::::::::	2026.1.0 (including)	2026.1.2 (excluding)
cpe:2.3:a:discourse:discourse::::::::	2026.2.0 (including)	2026.2.1 (excluding)
cpe:2.3:a:discourse:discourse:2026.3.0::::latest:::

To consult the complete list of CPE names with products and versions, see this page

CVE-2026-33395

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools