CVE-2026-72720

Medium

Description

Discourse is an open-source discussion platform. Prior to 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1, Discourse has HTML injection in PrettyText.format_for_email because cooked attribute values are reparsed as markup. Crafted Vimeo iframe sources, secure-upload URLs or dimensions, and hashtag data-slug values can cause decoded attribute text to be reinterpreted as HTML. The vulnerable conversion also fails to strictly validate the Vimeo iframe host and path, allowing non-Vimeo allowlisted iframes to be converted. This issue is fixed in versions 2026.1.7, 2026.6.2, 2026.7.1, and 2026.8.0-latest.1.

SeverityMedium
CVSS6.4
Exploit probability—
ProductDiscourse
PublishedAug 10, 2026
First seenAug 10, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
discourse discourse< 2026.1.7, >= 2026.6.0-latest, < 2026.6.2, >= 2026.7.0-latest, < 2026.7.1, >= 2026.8.0-latest, < 2026.8.0-latest.1—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.

CVE-2026-72720 · Discourse · Dark Radar