Description (CNA)
Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, an unauthenticated attacker could send a single request with a crafted color_scheme_id (or dark_scheme_id) cookie to inject arbitrary HTML into a Discourse page. Because the cookie value was rendered into a color scheme tag without escaping, the attacker could break out of the attribute and inject a tag that bypassed Discourse's nonce-based Content Security Policy, resulting in arbitrary JavaScript execution in visitors' browsers. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| discourse / discourse | affected < 2026.1.6; affected >= 2026.5.0-latest, < 2026.5.2; affected >= 2026.6.0-latest, < 2026.6.1 |
CWE
CWE-79
References
ADP enrichment
No English description supplied.
No references supplied.