Vulnerability in Broadcom Rabbitmq Server
CVE-2026-67419
RabbitMQ is a messaging and streaming broker. Prior to 4.3.5, an authenticated user who can bind a queue to a topic exchange and publish to it can use consecutive # segments in a binding key to make both topic matchers revisit the same trie-node and routing-key-suffix states without memoization. The matcher materializes duplicate destinations before deduplication, causing combinatorial CPU work and memory pressure that can disrupt routing for all tenants. This vulnerability is fixed in 4.3.5.
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:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (31.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 31st percentile — 31.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.004 · change: +0.000
Affected products
- Broadcom Rabbitmq Server
- Rabbitmq Rabbitmq-Server — versions < 4.3.5
Weakness classification (CWE)
References
- https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-h964-v5mf-22cq (Exploit, Mitigation, Vendor Advisory)
- https://github.com/rabbitmq/rabbitmq-server/commit/c5ed7c4e97e02be688730803604cc7a88dbe4864 (Patch)
- https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5 (Release Notes)
Frequently asked questions
- What is CVE-2026-67419?
- CVE-2026-67419 is a medium-severity vulnerability in Broadcom Rabbitmq Server, classified under Inefficient Algorithmic Complexity. CVSS score: 6.5/10. Published 2026-09-25.
- How severe is CVE-2026-67419?
- Medium severity. CVSS v3 base score is 6.5 out of 10.