Description
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.
Affected products
broadcom: rabbitmq server
References4
- github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-h9… Vendor AdvisoryExploitMitigation
- github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-h9… Vendor AdvisoryExploitMitigation
- github.com/rabbitmq/rabbitmq-server/commit/c5ed7c4e97e02be68873… Patch
- github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.5 Release Notes
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/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:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 31 · as of 9 November 2026
- CWE
- CWE-407CWE-1333
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