Rabbitmq server: RabbitMQ is a messaging and streaming broker. (CVE-2026-66074)
Description
CVE-2026-66074 affects RabbitMQ messaging broker versions prior to 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0. The vulnerability arises from the match_value/3 function passing user-supplied regular expressions to re:run without a match_limit, causing excessive CPU consumption when processing large resource sets. This can lead to significant CPU exhaustion and scheduler saturation via normal API use by any user with the management tag. The issue is fixed in the specified versions.
CVSS v4.0
Affected software
pkg:deb/ubuntu/rabbitmq-server?arch=source&distro=esm-infra-legacy/xenialpkg:deb/ubuntu/rabbitmq-server?arch=source&distro=esm-infra/bionicpkg:deb/ubuntu/rabbitmq-server?arch=source&distro=esm-infra/focalpkg:deb/ubuntu/rabbitmq-server?arch=source&distro=jammypkg:deb/ubuntu/rabbitmq-server?arch=source&distro=noblepkg:deb/ubuntu/rabbitmq-server?arch=source&distro=resoluteRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
RabbitMQ versions before 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0 contain a vulnerability where the match_value/3 function executes user-supplied regular expressions without a match_limit option, running once per resource in the result set. OTP's default 10 million match_limit caps each call to about 100-200ms, but with large sets (e.g., 5000 queues), a single request can consume over 12 minutes of CPU time. Parallel requests can saturate Erlang schedulers, leading to denial of service. The vulnerability is exploitable by any user with the management tag via the use_regex=true option on list endpoints, which is a supported feature.
Potential Impact
Exploitation of this vulnerability can cause significant CPU resource exhaustion on RabbitMQ servers, potentially leading to denial of service conditions. Attackers with management tag privileges can trigger prolonged CPU usage by submitting crafted regular expressions, impacting system availability and performance. There is no indication of data confidentiality or integrity compromise.
Mitigation Recommendations
This vulnerability is fixed in RabbitMQ versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0. Users should upgrade to these or later versions to remediate the issue. No additional mitigation is required if running these fixed versions.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- UBUNTU-CVE-2026-66074
- Osv Schema Version
- 1.7.0
- Ecosystems
- ["Ubuntu:Pro:16.04:LTS","Ubuntu:Pro:18.04:LTS","Ubuntu:Pro:20.04:LTS","Ubuntu:22.04:LTS","Ubuntu:24.04:LTS","Ubuntu:26.04:LTS"]
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ad3f5af2cdf04f65666281d
Added to database: 10/17/2026, 22:24:47 UTC
Last enriched: 10/18/2026, 00:08:47 UTC
Last updated: 10/18/2026, 00:08:47 UTC
Views: 3
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