CVE-2026-44786: Discourse

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Discourse is an open-source discussion platform. From versions 2026.1.0-latest to before 2026.1.4, 2026.3.0-latest to before 2026.3.1, and 2026.4.0-latest to before 2026.4.1, chat events for public category channels are published to MessageBus without permission scoping, so any MessageBus subscriber without chat enabled could receive chat message payloads in real time. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.

Affected products

• Discourse Discourse: before 2026.1.0 (fixed in 2026.1.0); from 2026.1.0, before 2026.1.4 (fixed in 2026.1.4); from 2026.3.0, before 2026.3.1 (fixed in 2026.3.1); from 2026.4.0, before 2026.4.1 (fixed in 2026.4.1); version 2026.5.0 only

Published 2026-06-12. Last modified 2026-06-17.