RabbitMQ: Atom exhaustion: to_atom on runtime-parameter component
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 1 fixed, 1 without a fix
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.
Summary
RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, The runtime-parameters lookup path coerces the URL :component segment to an atom with rabbit_data_coercion:to_atom/1 in lookup_component/1 (deps/rabbit/src/rabbit_runtime_parameters.erl), creating a new atom for any previously unseen value. A safe helper, rabbit_registry:binary_to_type/1, which uses binary_to_existing_atom with a catch, already exists but is not used at this call site. lookup_component/1 calls rabbit_data_coercion:to_atom(Component) on the :component segment of the request URL, converting an attacker-supplied string into a new atom. Because the Erlang atom table is bounded and atoms are never garbage collected, an authorized policymaker issuing roughly one million requests with distinct component values can exhaust the atom table and crash the node, resulting in a denial of service. Preconditions include Exploitation requires policymaker privileges and roughly one million requests.. This issue is fixed in versions 4.2.7 and 4.3.1.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA rabbitmq-server (rabbitmq) Fixed in 4.2.7, 4.3.1
Red Hat 1 advisory
- RHSA-2026:67552 Released 2026-09-15 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images rabbitmq-server4.3-4.3.6-1.hum1@aarch64, rabbitmq-server4.3-4.3.6-1.hum1@src, rabbitmq-server4.3-4.3.6-1.hum1@x86_64
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Hardened Images | Affected | No fix planned: Will not fix |
| Red Hat Hardened Images | Fixed | RHSA-2026:67552 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-67228
- 2026-10-30 CVSS score added · NVD
References
More rabbitmq vulnerabilities
- TI-2026-41154 Improper authentication in rabbitmq-server CVSS 3.1CRITICAL 10.0
- TI-2026-41149 RabbitMQ: UNC SSRF affecting the management UI on Windows CVSS 3.1CRITICAL 10.0
- TI-2026-41158 Resource allocation without limits in rabbitmq-server CVSS 3.1HIGH 7.5
- TI-2026-47695 RabbitMQ: OAuth2 Client Secret Exposed via Unauthenticated JavaScript Endpoint CVSS 4.0HIGH 8.2
- TI-2026-47694 RabbitMQ: JWKS Fetch Ignores HTTP Response Status Code - Signing Key Destruction Causes Authentication DoS CVSS 4.0HIGH 8.2
- TI-2026-45167 RabbitMQ Java client: Unvalidated Class.forName in JSON-RPC ProcedureDescription enables arbitrary class loading CVSS 4.0HIGH 7.5
Sources
- CVE-2026-67228 · CVE Program
- CVE-2026-67228 · NVD
- FIRST EPSS
- CVE-2026-67228 · Red Hat security data · CC BY 4.0
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