CVE-2026-55424
Medium
Description
Discourse is an open-source discussion platform. Prior to 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5, a topic "featured link" was not sufficiently normalized and escaped before being rendered in the topic list, allowing a user who can set a featured link to inject JavaScript when default Content Security Policy protections were modified or disabled. This issue is fixed in versions 2026.6.0, 2026.5.1, 2026.4.2, and 2026.1.5.
SeverityMedium
CVSS5.4
Exploit probability36. percentile0.4%
Product
Discourse
PublishedJul 9, 2026
First seenJul 9, 2026
Weakness typeCWE-79Cross-site scripting (XSS)
How to fix
Update
- discourse discourse2026.1.5, 2026.4.2, 2026.5.1 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| discourse discourse | 2026.1.0 ≤ v < 2026.1.5, 2026.4.0 ≤ v < 2026.4.2, 2026.5.0 ≤ v < 2026.5.1, 2026.6.0 | 2026.1.5, 2026.4.2, 2026.5.1 |
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