CVE-2026-67419: CWE-407: Inefficient Algorithmic Complexity in rabbitmq rabbitmq-server
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.
AI Analysis
Technical Summary
RabbitMQ versions before 4.3.5 contain a vulnerability (CVE-2026-67419) where an authenticated user with permissions to bind queues and publish to topic exchanges can exploit inefficient algorithmic complexity in the topic matcher. By using consecutive # segments in a binding key, the topic matcher revisits the same trie-node and routing-key-suffix states multiple times without memoization, causing duplicate destination materialization before deduplication. This leads to combinatorial CPU and memory resource consumption, potentially disrupting routing for all tenants sharing the broker. The vulnerability is addressed and fixed in rabbitmq-server version 4.3.5.
Potential Impact
An attacker with authenticated access and the ability to bind queues and publish to topic exchanges can cause significant CPU and memory resource exhaustion on the RabbitMQ server. This can disrupt message routing for all tenants on the broker, potentially leading to denial of service conditions. The impact is high due to the potential for widespread disruption of messaging services.
Mitigation Recommendations
This vulnerability is fixed in rabbitmq-server version 4.3.5. Users should upgrade to version 4.3.5 or later to remediate this issue. No other mitigation or temporary workaround is indicated in the available data.
CVE-2026-67419: CWE-407: Inefficient Algorithmic Complexity in rabbitmq rabbitmq-server
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.
CVSS v4.0
Score 7.1high
Affected software
rabbitmq
rabbitmq-server
pkg:github/rabbitmq/rabbitmq-serverRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
RabbitMQ versions before 4.3.5 contain a vulnerability (CVE-2026-67419) where an authenticated user with permissions to bind queues and publish to topic exchanges can exploit inefficient algorithmic complexity in the topic matcher. By using consecutive # segments in a binding key, the topic matcher revisits the same trie-node and routing-key-suffix states multiple times without memoization, causing duplicate destination materialization before deduplication. This leads to combinatorial CPU and memory resource consumption, potentially disrupting routing for all tenants sharing the broker. The vulnerability is addressed and fixed in rabbitmq-server version 4.3.5.
Potential Impact
An attacker with authenticated access and the ability to bind queues and publish to topic exchanges can cause significant CPU and memory resource exhaustion on the RabbitMQ server. This can disrupt message routing for all tenants on the broker, potentially leading to denial of service conditions. The impact is high due to the potential for widespread disruption of messaging services.
Mitigation Recommendations
This vulnerability is fixed in rabbitmq-server version 4.3.5. Users should upgrade to version 4.3.5 or later to remediate this issue. No other mitigation or temporary workaround is indicated in the available data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-29T15:02:20.412Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab6a5d4f7a7c54106055632
Added to database: 09/25/2026, 16:48:20 UTC
Last enriched: 09/25/2026, 17:02:54 UTC
Last updated: 09/26/2026, 02:45:24 UTC
Views: 13
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