CVE-2026-27152
DM Communication-Preference Bypass in Discourse Allows Unauthorized Messaging
Publication date: 2026-02-26
Last updated on: 2026-03-02
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| discourse | discourse | to 2025.12.2 (exc) |
| discourse | discourse | From 2026.1.0 (inc) to 2026.1.1 (exc) |
| discourse | discourse | 2026.2.0 |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-284 | The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-27152 is a vulnerability in the Discourse open source discussion platform that allows a user to bypass direct message (DM) communication preferences. Specifically, when adding members to an existing DM channel using the Chat::AddUsersToChannel function, a user can add targets who have blocked, ignored, or muted them. This bypass circumvents the per-recipient private message restrictions that are normally enforced during the creation of DM channels.
How can this vulnerability impact me? :
This vulnerability can impact users by allowing unwanted communication despite their preferences to block, ignore, or mute certain users. Attackers can add users who have blocked them into existing DM channels, potentially exposing users to unwanted messages or interactions that they intended to avoid. This improper access control could lead to privacy concerns and a degraded user experience.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
The recommended immediate step to mitigate this vulnerability is to upgrade the Discourse software to one of the patched versions: 2025.12.2, 2026.1.1, or 2026.2.0.
No known workarounds are available, so applying the update is the primary method to address the issue.