CVE-2026-67411Public exploitNetwork attack vectorHinoki check available

Authenticated MQTT access via discarded proxy address

Published Sep 25, 2026 · Updated Sep 25, 2026

Incorrect authorization in affected RabbitMQ Server releases allows remote authenticated users to bypass loopback-only MQTT account restrictions. The Web MQTT handler unwraps a proxy-aware socket before rabbit_mqtt_processor:init/4 derives PeerIp, so loopback_users evaluates the trusted frontend address instead of the original client. A reachable trusted PROXY Protocol frontend, enabled MQTT or Web MQTT, and valid credentials for a loopback-restricted account are required; password authentication remains enforced, while the account's permitted messages and resources become accessible.

CVSS severity6.0
Medium
EPSS probability0.32%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Incorrect authorization in affected RabbitMQ Server releases allows remote authenticated users to bypass loopback-only MQTT account restrictions. The Web MQTT handler unwraps a proxy-aware socket before rabbit_mqtt_processor:init/4 derives PeerIp, so loopback_users evaluates the trusted frontend address instead of the original client. A reachable trusted PROXY Protocol frontend, enabled MQTT or Web MQTT, and valid credentials for a loopback-restricted account are required; password authentication remains enforced, while the account's permitted messages and resources become accessible.

The record

CVE
CVE-2026-67411
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
RabbitMQ
Product
RabbitMQ Server
Classifications
CWE-863, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 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=>= 3.13.0, < 3.13.18
  2. Affected versionversion=>= 4.0.0, < 4.0.23
  3. Affected versionversion=>= 4.1.0, < 4.1.14
  4. Affected versionversion=>= 4.2.0, < 4.2.9
  5. Affected versionversion=>= 4.3.0, < 4.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

RabbitMQ · RabbitMQ Serverversion=>= 3.13.0, < 3.13.18; version=>= 4.0.0, < 4.0.23; version=>= 4.1.0, < 4.1.14; version=>= 4.2.0, < 4.2.9; version=>= 4.3.0, < 4.3.3

Published CVSS scores

6.0GitHubCVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA: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.

Activity data is delayed. The latest report is Sep 28, 2026.

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

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1190Exploit Public-Facing Application

Public exploit references

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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