CVE-2026-67226Public exploitNetwork attack vector

Admin-triggered node crash via unbounded atom creation

Published Sep 25, 2026 · Updated Sep 25, 2026

Resource exhaustion in RabbitMQ Server allows remote authenticated users to crash a broker node through crafted user tags. The set_tags/2 path in rabbit_auth_backend_internal maps every supplied tag through rabbit_data_coercion:to_atom/1, permanently interning millions of attacker-chosen atoms until the Erlang VM exhausts its atom table. An administrator-tagged account and the management API or definitions import path are required, and exploitation interrupts service for every tenant on the node.

CVSS severity6.9
Medium
EPSS probability0.35%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in RabbitMQ Server allows remote authenticated users to crash a broker node through crafted user tags. The set_tags/2 path in rabbit_auth_backend_internal maps every supplied tag through rabbit_data_coercion:to_atom/1, permanently interning millions of attacker-chosen atoms until the Erlang VM exhausts its atom table. An administrator-tagged account and the management API or definitions import path are required, and exploitation interrupts service for every tenant on the node.

The record

CVE
CVE-2026-67226
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
RabbitMQ
Product
RabbitMQ Server
Classifications
CWE-400, T1499
Attack vector
network
Privileges
admin

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=>= 4.0.0, < 4.0.22
  2. Affected versionversion=>= 4.1.0, < 4.1.14
  3. Affected versionversion=>= 4.2.0, < 4.2.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

RabbitMQ · RabbitMQ Serverversion=>= 4.0.0, < 4.0.22; version=>= 4.1.0, < 4.1.14; version=>= 4.2.0, < 4.2.7

Published CVSS scores

6.9RabbitMQCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499Endpoint Denial of Service

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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