SECURELYN

CVE-2026-67231

RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, The trust-store plugin installs a verify_fun that overrides {bad_cert, unknown_ca} / {bad_cert, selfsigned_peer} when the presented cert "matches" a whitelisted one. The match key is extract_issuer_id/1 → public_key:pkix_issuer_id/2 → {IssuerName, SerialNumber} , both fields are taken verbatim from the presented certificate body and contain no public-key, SKI, fingerprint or signature material. is_whitelisted/1 is a pure ets:member lookup; the stored full DER is used only for list/0 disp…

Scores

9.1
CVSS 9.1 out of 10, critical severity.
0.2%
EPSS 0.2% chance of exploitation in the next 30 days.

The facts

Published
23 September 2026
Last changed
29 September 2026
NVD status
Undergoing Analysis
Severity
Critical, CVSS 9.1 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/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…
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.2% chance of exploitation activity in the next 30 days (percentile 15).

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References