What is CVE-2026-72723?

CVE-2026-72723 is a medium-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-08-10.

How severe is CVE-2026-72723?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Auth bypass in Discourse

CVE-2026-72723

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous_default_navigation_menu_tags serializes tags from SiteSetting.default_navigation_menu_tags without applying DiscourseTagging.filter_visible for the anonymous viewer. An unauthenticated user can retrieve restricted tag names and descriptions through /site.json when those tags are limited by inaccessible categories, category tag groups, or tag-group permissions. 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 2026-08-10 · last modified 2026-09-08.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.005 (42.1th percentile), scored 2026-09-26.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 42nd percentile — 42.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · 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)

CWE-862 — Missing Authorization

References

Frequently asked questions

What is CVE-2026-72723?: CVE-2026-72723 is a medium-severity vulnerability in Discourse, classified under Missing Authorization. CVSS score: 5.3/10. Published 2026-08-10.
How severe is CVE-2026-72723?: Medium severity. CVSS v3 base score is 5.3 out of 10.