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TI-2026-47542 Aliases CVE-2026-67226

RabbitMQ: Admin-only atom exhaustion: PUT /api/users tags list

Priority MEDIUM 64CWE-400Published · Updated

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, 5 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. From 4.0.0 until 4.0.22 and 4.1.14 and 4.2.7, Admin-only atom exhaustion: PUT /api/users tags list. settags/2 maps rabbitdatacoercion:toatom/1 over the user's tags list. The 20 MB management body limit fits ~3-4M short tag strings. An administrator can crash the node in a single request by creating a user (or importing definitions) with ~1M unique tag administrator. This issue is fixed in versions 4.0.22 and 4.1.14 and 4.2.7.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00389 33rd percentileScored 2026-11-07
Fix Partial rabbitmq-server (rabbitmq): 4.0.22, 4.1.14, 4.2.7Red Hat: 1 advisoryRed Hat: 1 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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

VendorProductAffected versionsFixed inStatusSource
rabbitmqrabbitmq-server4.0.0 to before 4.0.22; 4.1.0 to before 4.1.14; 4.2.0 to before 4.2.74.0.22, 4.1.14, 4.2.7Patch availableCNA
  • rabbitmq-server Vendorrabbitmq Affected 4.0.0 to before 4.0.22; 4.1.0 to before 4.1.14; 4.2.0 to before 4.2.7 Fixed in 4.0.22, 4.1.14, 4.2.7 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*4.0.0 to before 4.0.22; 4.1.0 to before 4.1.14; 4.2.0 to before 4.2.7VulnerableBroadcom
  • cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:* Versions 4.0.0 to before 4.0.22; 4.1.0 to before 4.1.14; 4.2.0 to before 4.2.7 Vulnerable ·Broadcom

Remediation

  • Fix · CNA rabbitmq-server (rabbitmq) Fixed in 4.0.22, 4.1.14, 4.2.7

Red Hat 1 advisory

  • RHSA-2026:67552 Released 2026-09-15 · Red Hat rating Important
    Red 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 →

ProductStatusPlan or fix
Red Hat Hardened ImagesAffectedNo fix planned: Will not fix
Red Hat OpenStack Platform 13 (Queens)AffectedNo fix planned: Out of support scope
Red Hat OpenStack Platform 16.2AffectedNo fix planned: Out of support scope
Red Hat OpenStack Platform 17.1AffectedNo fix planned: Out of support scope
Red Hat OpenStack Platform 18.0AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:67552

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-67226
  2. 2026-10-18 Fix available: RHSA-2026:67552 · Red Hat
  3. 2026-10-18 Fix available: Red Hat Hardened Images · Red Hat
  4. 2026-10-18 CVSS score added · Red Hat
  5. 2026-10-20 CVSS score added · NVD

References

Patch 2

Advisory 1

  • 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
See all 100 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences