Auth bypass in Discourse

CVE-2026-72732

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, the discourse_templates endpoint exposed hidden tag names because DiscourseTemplates::TemplatesSerializer in plugins/discourse-templates/app/serializers/discourse_templates/templates_serializer.rb did not filter tags through the request Guardian. The serializer did not respect tag group permissions, allowing users to see tags they were not permitted to view. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.

Vulnerability class: Broken Access Control

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 25th percentile — 24.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-72732: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.001

Affected products

  • Discourse — versions < 2026.1.6, >= 2026.5.0-latest, < 2026.5.2, >= 2026.6.0-latest, < 2026.6.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-72732?
CVE-2026-72732 is a medium-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 4.3/10. Published 2026-08-10.
How severe is CVE-2026-72732?
Medium severity. CVSS v3 base score is 4.3 out of 10.