Vulnerability · Published Sep 23, 2026 · Assigned by GitHub_M

CVE-2026-66074RabbitMQ: ReDoS via management API ?name= filter

Medium 6.0

In plain English

A medium-severity regular-expression denial of service in rabbitmq-server from rabbitmq. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 33% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 4.0)6.0Medium

Exploit odds (30 days)0.4%top 67.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, match_value/3 passes the user-supplied ?name= regular expression to re:run with no match_limit option, and executes it once per resource in the result set. OTP's default 10M match_limit caps each call at roughly 100-200ms, but the regex runs once per resource in the result set. With a large set, for example 5000 queues at 150ms each, a single request consumes 12 or more minutes of CPU. Parallel requests saturate the schedulers. The use_regex=true option is a supported feature on list endpoints, so this path is reachable through normal API use. Preconditions include Any user with the management tag can exploit this.. This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	rabbitmq-server	no fix listed	DEBIAN-CVE-2026-66074
Debian:13	rabbitmq-server	no fix listed	DEBIAN-CVE-2026-66074
Debian:14	rabbitmq-server	4.3.0-2	DEBIAN-CVE-2026-66074
Ubuntu:22.04:LTS	rabbitmq-server	no fix listed	UBUNTU-CVE-2026-66074
Ubuntu:24.04:LTS	rabbitmq-server	no fix listed	UBUNTU-CVE-2026-66074
Ubuntu:26.04:LTS	rabbitmq-server	no fix listed	UBUNTU-CVE-2026-66074

Affected products (as reported)

Vendor	Product	Versions
rabbitmq	rabbitmq-server	>= 3.13.0, < 3.13.15>= 4.0.0, < 4.0.20>= 4.1.0, < 4.1.11>= 4.2.0, < 4.2.6

Weakness: CWE-1333 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

References

https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-rg5q-vcgf-rfh7 x_refsource_CONFIRM
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6 x_refsource_MISC
https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0 x_refsource_MISC