Vulnerability in Broadcom Rabbitmq Server
CVE-2026-67242
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.9 and 4.3.3, OAuth2 isinteger(Exp) guard skips token-expiry checks for float exp. validatetokenexpiry/1 (lines 208-214) and expirytimestamp/1 (138-144) both guard with 'when isinteger(Exp)' and fall through to ok/never for float values. josejwt:verify validates only the signature, not exp. With float exp, no expiry validation occurs anywhere in the If the IdP emits exp as a JSON float (RFC 7519 permits fractional NumericDate), both the login-time expiry check and the mid-connection disconnect timer are silently skipped , an already-expired token is accepted, and connections never time OAuth2 backend enabled IdP emits float exp (uncommon; mainstream IdPs emit integers) Attacker possesses a previously-valid signed. This issue is fixed in versions 4.2.9 and 4.3.3.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (28.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.003 · change: -0.001
Affected products
- Broadcom Rabbitmq Server
- Rabbitmq Rabbitmq-Server — versions >= 4.2.0, < 4.2.9, >= 4.3.0, < 4.3.3
Weakness classification (CWE)
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-rrj4-g94f-rqj9 (Vendor Advisory)
- https://github.com/rabbitmq/rabbitmq-server/commit/d10a369a96658d0fba1050bd43c732e58fcf28fd (Patch)
- https://github.com/rabbitmq/rabbitmq-server/commit/f189a8824c9efbce46bd9438fcdbda4521cfc923 (Patch)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.9 (Release Notes)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.3 (Release Notes)
Frequently asked questions
- What is CVE-2026-67242?
- CVE-2026-67242 is a medium-severity vulnerability in Broadcom Rabbitmq Server, classified under Insufficient Session Expiration. CVSS score: 5.4/10. Published 2026-09-25.
- How severe is CVE-2026-67242?
- Medium severity. CVSS v3 base score is 5.4 out of 10.