CVE-2026-44783

Undergoing Analysis Undergoing Analysis - In Progress

Authentication Bypass in Discourse Whisper Channel

Publication date: 2026-06-12

Last updated on: 2026-06-15

Assigner: GitHub, Inc.

Description

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, a flaw in how replies to whisper posts are handled allows authenticated users outside the groups configured in whispers_allowed_groups to post into a topic's staff-only whisper channel. The injected content is visible to whisperers (typically staff) alongside legitimate whispers. Only sites that have whispers enabled are affected. This issue has been patched in versions 2026.1.4, 2026.3.1, 2026.4.1, and 2026.5.0-latest.1.

CVSS Scores

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Meta Information

Published

2026-06-12

Last Modified

2026-06-15

Generated

2026-07-03

AI Q&A

2026-06-13

EPSS Evaluated

2026-07-01

NVD

CVE-2026-44783

Affected Vendors & Products

Vendor	Product	Version / Range
discourse	discourse	From 2026.1.0 (inc) to 2026.1.4 (exc)
discourse	discourse	From 2026.3.0 (inc) to 2026.3.1 (exc)
discourse	discourse	From 2026.4.0 (inc) to 2026.4.1 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-284	The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

Attack-Flow Graph

Executive Summary

This vulnerability exists in the Discourse open-source discussion platform in certain versions before 2026.1.4, 2026.3.1, and 2026.4.1. It is caused by a flaw in how replies to whisper posts are handled. Specifically, authenticated users who are not part of the groups configured in whispers_allowed_groups can post messages into a topic's staff-only whisper channel.

These injected messages become visible to the whisperers, who are typically staff members, alongside legitimate whispers. This means unauthorized users can insert content into private staff discussions if the whispers feature is enabled on the site.

Impact Analysis

The impact of this vulnerability is that unauthorized authenticated users can post messages into staff-only whisper channels, potentially leading to information disclosure or manipulation of private staff communications.

Since the injected content is visible to staff members, it could cause confusion, misinformation, or disruption within staff discussions. This could undermine trust in the platform's privacy controls and potentially expose sensitive internal communications.

Mitigation Strategies

To mitigate this vulnerability, you should upgrade your Discourse installation to one of the patched versions: 2026.1.4, 2026.3.1, 2026.4.1, or 2026.5.0-latest.1.

Additionally, ensure that the whispers feature is properly configured and consider disabling it if it is not required, as only sites with whispers enabled are affected.

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