Discourse is an open-source platform for community discussion. In Discourse before versions 2.7.8 and 2.8.0.beta5, a user's read state for a topic such as the last read post number and the notification level is exposed.
https://github.com/discourse/discourse/security/advisories/GHSA-gq2h-qhg2-phf9
https://github.com/discourse/discourse/commit/aed65ec16d38886d7be7209d8c02df4ffd4937a4
Source: Mitre, NVD
Published: 2021-08-13
Updated: 2026-06-17
Base Score: 4.3
Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N
Severity: Medium
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
EPSS: 0.00219