CVE-2026-72722
Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup do not consistently enforce Guardian.can_see? checks when processing internal links. An authenticated user can submit links to restricted topics, private messages, or hidden posts and receive canonicalized slugs or titles in the composer_messages duplicate_lookup response even though the targets are not visible to that user. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.
Attack profile
The conditions required to exploit this vulnerability and its potential impact.
Affected products
Product applicability statements supplied with the NVD record.
Weakness classification
CWE categories help security teams group the underlying software weakness.
Source references
External advisories, patches and technical reports attached to this CVE record.