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, protected tag bypass via bulk-delete. dELETE /api/users/:name refuses to delete users tagged protected (rabbitmgmtwmuser:deleteresource/2 checks isprotecteduser). POST /api/users/bulk-delete iterates the supplied username list and calls rabbitauthbackendinternal:deleteuser/2 directly , that function has no protected-tag check , so the guard is silently An administrator can delete protected-tagged service accounts via the bulk endpoint, bypassing a safeguard the test suite confirms is rabbitmqmanagement enabled Attacker has the administrator tag A protected-tagged user. This issue is fixed in versions 3.13.15 and 4.0.20 and 4.1.11 and 4.2.6.
CVE-2026-66078
This low-severity CVE scores 2.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (27th percentile of EPSS-scored CVEs). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 2.1
- EG Score
- 2.1LOWmedium confidence
- EG Risk
- 40EG Risk 40/100CISA SSVC
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity21% × 45%Exploitation40% × 40%Automatability100% × 15%CISA SSVC: Track at low, Track* at medium and Attend at high mission impact.Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high. - EPSS PROB
- 0.4%
- EPSS %ILE
- 27th
- KEV
- Not listed
CISA SSVCTrack at low, Track* at medium and Attend at high mission impact.
A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table
Published
September 25, 2026
Last Modified
September 29, 2026
References (4)
- security-advisories@githubhttps://github.com/rabbitmq/rabbitmq-server/commit/e5b890a64b42ec1f79a8e9d735512150cf77479c
- security-advisories@githubhttps://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6
- security-advisories@githubhttps://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-j9m2-hw6x-rqr9
- 134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-j9m2-hw6x-rqr9
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 13× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-10-03 14:26 UTCEPSS rescore
- 2026-10-03 00:48 UTCEG score recompute
- 2026-10-02 17:56 UTCEPSS rescore
- 2026-10-01 19:50 UTCEPSS rescore
- 2026-09-30 15:03 UTCEPSS rescore
- 2026-09-29 20:31 UTCEG score recompute
- 2026-09-29 19:38 UTCEG score recompute
- 2026-09-28 14:44 UTCEG score recompute
- 2026-09-28 13:51 UTCEPSS rescore
- 2026-09-26 15:59 UTCEPSS rescore
- 2026-09-25 17:37 UTCEG score recompute
- 2026-09-25 16:24 UTCEG score recompute
- 2026-09-25 16:24 UTCMITRE cvelistV5first tracked
Related CVEs(same CWE)
Frequently asked(5)
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-66078
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