Discourse has a bypass of official warnings messages by non-… (CVE-2026-27491)

Summary

Discourse has a bypass of official warnings messages by non-staff users

Original description

The description as published by the source.

Discourse is an open-source discussion platform. Prior to versions 2026.3.0, 2026.2.1, and 2026.1.2, a type coercion issue in a post actions API endpoint allowed non-staff users to issue warnings to other users. Warnings are a staff-only moderation feature. The vulnerability required the attacker to be a logged-in user and to send a specifically crafted request. No data exposure or privilege escalation beyond the ability to create unauthorized user warnings was possible. Versions 2026.3.0, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.

Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV

Affected packages

Bitnami discourse

[{"type":"SEMVER","events":[{"introduced":"2026.1.0"},{"fixed":"2026.1.2"},{"introduced":"2026.2.0"},{"fixed":"2026.2.1"},{"introduced":"2026.3.0"},{"fixed":"2026.3.0"}]}]

References

advisory github.com
patch github.com
patch github.com
patch github.com
web nvd.nist.gov