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TI-2026-47044 Aliases CVE-2026-66067

RabbitMQ: Stream protocol skips per vhost per user connection limits

Priority LOW 27CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
Present
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-770.

Summary

RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, The stream open handler calls only check_vhost_access; it omits the node/vhost/user connection-limit checks that rabbit_reader performs for AMQP. A developer %% FIXME comment at the cited line explicitly acknowledges the gap. No compensating enforcement exists in connection tracking or elsewhere in rabbitmq_stream. An authenticated tenant can fully bypass operator-configured per-user and per-vhost connection caps by connecting via port 5552 instead of 5672. Preconditions include rabbitmq_stream plugin enabled Authenticated stream-protocol credentials Operator relies on per-user/per-vhost connection limits for tenant isolation. This issue is fixed in versions 4.2.7 and 4.3.1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00437 38th percentileScored 2026-11-07
Fix Partial rabbitmq-server (rabbitmq): 4.2.7, 4.3.1Red Hat: 1 advisoryRed Hat: 1 fixed, 1 without a fix

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

VendorProductAffected versionsFixed inStatusSource
rabbitmqrabbitmq-server4.2.0 to before 4.2.7; 4.3.0 to before 4.3.14.2.7, 4.3.1Patch availableCNA
  • rabbitmq-server Vendorrabbitmq Affected 4.2.0 to before 4.2.7; 4.3.0 to before 4.3.1 Fixed in 4.2.7, 4.3.1 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:*4.2.0 to before 4.2.7; 4.3.0 to before 4.3.1VulnerableBroadcom
  • cpe:2.3:a:broadcom:rabbitmq_server:*:*:*:*:*:*:*:* Versions 4.2.0 to before 4.2.7; 4.3.0 to before 4.3.1 Vulnerable ·Broadcom

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 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 Hardened ImagesFixed RHSA-2026:67552

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66067
  2. 2026-10-30 CVSS score added · NVD

References

Advisory 1

Other 2

  • 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