Cyber Resilience

CVE-2026-57218

Access Control in Broadcom Rabbitmq Server 4.2.0 – 4.2.6

Public PoCAccess Control
Published
10 July 2026
Modified
13 July 2026
Patch / advisory
CVSS Score v4 4.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.0035 28th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-57218 is a medium-severity Incorrect Authorization (CWE-863) vulnerability in Broadcom Rabbitmq Server. Its CVSS base score is 4.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Valid Accounts (T1078); ranked at the 28th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and AC-12 (Session Termination) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

RabbitMQ is a messaging and streaming broker. Prior to 4.2.6, RabbitMQ AMQP 0-9-1 allows an existing consumer to keep receiving messages after OAuth token expiry or connection.update_secret refresh to reduced scopes because existing consumers are not canceled or reauthorized at…

more

delivery time after the channel user state changes. This issue is fixed in version 4.2.6.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1078 Valid Accounts Stealth
Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion.
Why these techniques?

The vulnerability allows continued message consumption after OAuth token expiry or scope reduction, effectively permitting unauthorized access via stale/expired credentials (T1078: Valid Accounts).

Confidence: MEDIUM · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-57217Same product: Broadcom Rabbitmq Server
CVE-2026-44838Same product: Broadcom Rabbitmq Server
CVE-2026-57215Same product: Broadcom Rabbitmq Server
CVE-2026-57219Same product: Broadcom Rabbitmq Server
CVE-2026-57220Same product: Broadcom Rabbitmq Server
CVE-2026-57213Same product: Broadcom Rabbitmq Server
CVE-2026-57212Same product: Broadcom Rabbitmq Server
CVE-2026-44839Same product: Broadcom Rabbitmq Server
CVE-2026-57214Same product: Broadcom Rabbitmq Server
CVE-2025-50200Same product: Broadcom Rabbitmq Server

Affected Assets

broadcom
rabbitmq server
4.2.0 — 4.2.6

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-12 Session Termination
  • IA-11 Re-authentication
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces re-evaluation of authorizations at message delivery time after OAuth token expiry or scope reduction, which the CVE shows was not performed for existing consumers.

prevent

Requires automatic session/consumer termination or re-establishment when the channel user state changes due to token expiry or reduced scopes.

prevent

Forces re-authentication (and thus re-authorization) when security-relevant conditions such as token expiry or privilege reduction occur on an active AMQP channel.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-05 mostly match
prevents

Defining, enforcing, and reviewing access authorizations and least privilege directly prevents incorrect authorization checks.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

prevents

Enforcing policy-driven approval and role-change reviews stops incorrect or stale authorization decisions from remaining in effect after job changes or terminations.

prevents

By tying access rights to identity, device, location and classification, the control reduces the likelihood that an authorization decision will be based on an incorrect or bypassed policy.

References