--- title: "CVE-2026-66073\n | Ubuntu" description: Ubuntu is an open source software operating system that runs from the desktop, to the cloud, to all your internet connected things. url: https://ubuntu.com/security/CVE-2026-66073?format=md keywords: index, follow --- # CVE-2026-66073 Publication date 29 September 2026 Last updated 30 September 2026 --- Ubuntu priority **Medium** [Why this priority?](https://ubuntu.com/security/cves/about#priority ) Toggle side navigation ## Description RabbitMQ is a messaging and streaming broker. From 3.13.0 until 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6, Atom table exhaustion via management API node field. pUT /api/queues/:vhost/:name (and the exchanges and bindings endpoints) accepts a node JSON field. The value goes through rabbitnodes:make → listtoatom with no cluster membership check first. Each unique value permanently leaks one atom. A March 2026 refactoring (ea61ce2563) introduced safe helpers in rabbitmgmtnodes.erl (parsenodename, safeatom, and requirenodename, using binarytoexistingatom) and fixed several callers (QQ replica ops, wmauthattempts, wmnodememoryets, getsortreverse, and rabbitfederationmgmt), but getnode/1 in rabbitmgmtutil.erl:880-885, the primary vector used by directrequest/6, was not Roughly 900K requests crash the VM via systemlimit, and all tenants lose Any user with the management tag and one vhost, the lowest privilege This issue is fixed in versions 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6. ## Status Show unmaintained releases | Package | Ubuntu Release | Status | | --- | --- | --- | | rabbitmq-server | 26.04 LTS resolute | Needs evaluation | | 24.04 LTS noble | Needs evaluation | | 22.04 LTS jammy | Needs evaluation | | 20.04 LTS focal | Needs evaluation | | 18.04 LTS bionic | Needs evaluation | | 16.04 LTS xenial | Needs evaluation | --- * [How can I get the fixes?](https://ubuntu.com/security/cves/about#security) * [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses) ## Severity score breakdown CVSS version: CVSS v4.0 **Base score** 6.0 · Medium * Base metrics | Parameter | Value | | --- | --- | | Attack vector | Network | | Attack complexity | Low | | Attack requirements | Present | | Privileges required | Low | | User interaction | None | | Vulnerable system - Confidentiality impact | None | | Vulnerable system - Integrity impact | None | | Vulnerable system - Availability impact | High | | Subsequent system - Confidentiality impact | None | | Subsequent system - Integrity impact | None | | Subsequent system - Availability impact | None | * Scores | Parameter | Value | | --- | --- | | Base score | 6.0 · Medium | | Base + Threat score | - | | Base + Environmental score | - | | Base + Threat + Environmental score | - | **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 * [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-66073) * [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-66073) * [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-66073) * [Debian](https://security-tracker.debian.org/tracker/CVE-2026-66073) ### Other references * * * *