MEDIUM · 6.4

CVE-2026-72720

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 valu...

Vulnerability 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.

CVSS Score

6.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-72720?

CVE-2026-72720 is a vulnerability with a CVSS score of 6.4 (MEDIUM). 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 valu...

How severe is CVE-2026-72720?

CVE-2026-72720 has been rated MEDIUM with a CVSS base score of 6.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-72720?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.