CVE-2026-66074Network attack vectorHinoki check available

Service interruption via unbounded per-resource regex matching

Published Sep 23, 2026 · Updated Sep 23, 2026

Regular expression denial of service in RabbitMQ Server allows remote authenticated users to interrupt broker service through the management API. The match_value/3 function passes the user-controlled name filter to re:run without a match_limit and repeats the regex for every returned resource. A management-tagged account and a large result set are required; one request can consume minutes of CPU, while parallel requests can saturate schedulers.

CVSS severity6.0
Medium
EPSS probability0.33%
Next 30 days · Oct 18, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Regular expression denial of service in RabbitMQ Server allows remote authenticated users to interrupt broker service through the management API. The match_value/3 function passes the user-controlled name filter to re:run without a match_limit and repeats the regex for every returned resource. A management-tagged account and a large result set are required; one request can consume minutes of CPU, while parallel requests can saturate schedulers.

The record

CVE
CVE-2026-66074
Published
Sep 23, 2026
Updated
Sep 23, 2026
Vendor
RabbitMQ
Product
RabbitMQ Server
Classifications
CWE-1333, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 23, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 23, 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, < 3.13.15
  2. Affected versionversion=>= 4.0.0, < 4.0.20
  3. Affected versionversion=>= 4.1.0, < 4.1.11
  4. Affected versionversion=>= 4.2.0, < 4.2.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

RabbitMQ · RabbitMQ Serverversion=>= 3.13.0, < 3.13.15; version=>= 4.0.0, < 4.0.20; version=>= 4.1.0, < 4.1.11; version=>= 4.2.0, < 4.2.6

Published CVSS scores

6.0RabbitMQCVSS:4.0/AV:N/AC:L/AT:P/PR:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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