CVE-2026-66074

medium

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.

References

https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-rg5q-vcgf-rfh7

https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0

https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6

Details

Source: Mitre, NVD

Published: 2026-09-23

Updated: 2026-09-24

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 6.5

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Severity: Medium

CVSS v4

Base Score: 6

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

Severity: Medium

EPSS

EPSS: 0.0033