CVE-2026-44783Network attack vector

Staff-only post injection via unchecked whisper replies

Published Jun 12, 2026 · Updated Jun 12, 2026

Improper access control in Discourse allows remote authenticated users to inject posts into staff-only whisper channels through crafted replies. Reply processing fails to enforce membership in whispers_allowed_groups when the parent post is a whisper, allowing the reply to enter the same protected channel. Exploitation requires enabled whispers; injected content appears beside legitimate staff whispers without reported availability impact.

CVSS severity5.4
Medium
EPSS probability0.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Discourse allows remote authenticated users to inject posts into staff-only whisper channels through crafted replies. Reply processing fails to enforce membership in whispers_allowed_groups when the parent post is a whisper, allowing the reply to enter the same protected channel. Exploitation requires enabled whispers; injected content appears beside legitimate staff whispers without reported availability impact.

The record

CVE
CVE-2026-44783
Published
Jun 12, 2026
Updated
Jun 12, 2026
Vendor
Discourse
Product
Discourse
Classifications
CWE-284, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 2026.1.0-latest, < 2026.1.4
  2. Affected versionversion=>= 2026.3.0-latest, < 2026.3.1
  3. Affected versionversion=>= 2026.4.0-latest, < 2026.4.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=>= 2026.1.0-latest, < 2026.1.4; version=>= 2026.3.0-latest, < 2026.3.1; version=>= 2026.4.0-latest, < 2026.4.1

Published CVSS scores

5.4GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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