Vulnerability in Broadcom Rabbitmq Server
CVE-2026-67236
RabbitMQ is a messaging and streaming broker. From 4.2.0 until 4.2.8 and 4.3.2, a successful POST /login caused is_authorized/2 to set an auth cookie containing base64-encoded username:password credentials without HttpOnly, Secure, SameSite, or expiration protections. Because base64 is encoding rather than encryption, an attacker with same-origin cross-site scripting, an HTTP-readable network position, or local access to the browser cookie store could recover the actual login credentials; older browsers that treated an absent SameSite attribute as None also sent the cookie cross-site. This issue is fixed in versions 4.2.8 and 4.3.2.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.002 (5.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000
Affected products
- Broadcom Rabbitmq Server
- Rabbitmq Rabbitmq-Server — versions >= 4.2.0, < 4.2.8, >= 4.3.0, < 4.3.2
Weakness classification (CWE)
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-88vh-gx85-p36m (Exploit, Third Party Advisory)
- https://github.com/rabbitmq/rabbitmq-server/commit/df9e7f4c0afd311a672705f020d301efad355745 (Patch)
- https://github.com/rabbitmq/rabbitmq-server/commit/edf1fbc7217aaf736955d2e13c9534901a2e0778 (Patch)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.8 (Release Notes)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.2 (Release Notes)
Frequently asked questions
- What is CVE-2026-67236?
- CVE-2026-67236 is a medium-severity vulnerability in Broadcom Rabbitmq Server, classified under Cleartext Storage of Sensitive Information. CVSS score: 6.5/10. Published 2026-09-25.
- How severe is CVE-2026-67236?
- Medium severity. CVSS v3 base score is 6.5 out of 10.