CVE-2026-72726Network attack vectorHinoki check available

Authenticated information disclosure via unrestricted reply stream

Published Aug 10, 2026 · Updated Aug 10, 2026

Information disclosure in Discourse before 2026.1.6 allows remote authenticated users to read private AI bot replies through the reply stream. The publish_update method passes topic.allowed_user_ids to MessageBus; when that list is empty, MessageBus treats the stream as unrestricted. Exploitation requires a signed-in account and access to the AI bot reply channel; impact is limited to reading streamed conversation content.

CVSS severity6.5
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Information disclosure in Discourse before 2026.1.6 allows remote authenticated users to read private AI bot replies through the reply stream. The publish_update method passes topic.allowed_user_ids to MessageBus; when that list is empty, MessageBus treats the stream as unrestricted. Exploitation requires a signed-in account and access to the AI bot reply channel; impact is limited to reading streamed conversation content.

The record

CVE
CVE-2026-72726
Published
Aug 10, 2026
Updated
Aug 10, 2026
Vendor
Discourse
Product
Discourse
Classifications
CWE-200
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 10, 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=< 2026.1.6
  2. Affected versionversion=>= 2026.5.0, < 2026.5.2
  3. Affected versionversion=>= 2026.6.0, < 2026.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=< 2026.1.6; version=>= 2026.5.0, < 2026.5.2; version=>= 2026.6.0, < 2026.6.1

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/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-200Exposure of Sensitive Information to an Unauthorized Actor

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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