CVE-2026-33395
Discourse has stored click‑based XSS via Graphviz SVG javascript: links
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Discourse has stored click‑based XSS via Graphviz SVG javascript: links
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.
- Record
CVE-2026-33395- CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-13402
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.
- Record
EUVD-2026-13402- CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-33395- CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
Discourse has stored click‑based XSS via Graphviz SVG javascript: links
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.
- Record
CVE-2026-33395- CVSS 3.1
- 4.4 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSVBIT-discourse-2026-33395 No score
Discourse has stored click‑based XSS via Graphviz SVG javascript: links
Discourse is an open-source discussion platform. Prior to versions 2026.3.0, 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, 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.
- Record
BIT-discourse-2026-33395- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
discourseBitnami |
2026.1.0 up to 2026.1.2, 2026.2.0 up to 2026.2.1, 2026.3.0 up to 2026.3.0 | 2026.1.22026.2.12026.3.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-33395 is a medium vulnerability (CVSS 4.4) in Discourse, published March 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.22%, the 13th percentile. Fixed in discourse 2026.1.2.
References
github.com/discourse/discourse/security/advisories/GHSA-23c7-gq89-xm5v
nvd.nist.gov/vuln/detail/CVE-2026-33395