CVE-2026-66074: CWE-1333: Inefficient Regular Expression Complexity in rabbitmq rabbitmq-server
CVE-2026-66074 is a vulnerability in rabbitmq-server where inefficient regular expression handling in the management API can cause excessive CPU consumption. The issue occurs when user-supplied regular expressions are executed repeatedly without a match limit, leading to high CPU usage especially with large resource sets. This can result in long processing times and scheduler saturation. The vulnerability affects versions prior to 3.13.15, 4.0.20, 4.1.11, and 4.2.6. It requires a user with the management tag to exploit. The issue has been fixed in the specified versions.
AI Analysis
Technical Summary
RabbitMQ's management API allows users with the management tag to supply regular expressions via the ?name= parameter, which are passed to the Erlang re:run function without a match_limit option. Because the regex is executed once per resource in the result set, large numbers of resources (e.g., 5000 queues) can cause cumulative CPU consumption of many minutes per request. This inefficient regular expression complexity leads to potential denial of service by saturating CPU schedulers. The vulnerability is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Potential Impact
An attacker with management tag privileges can cause high CPU usage on the RabbitMQ server by submitting crafted regular expressions that are executed repeatedly across many resources. This can degrade server performance and potentially lead to denial of service conditions due to scheduler saturation. There is no indication of data compromise or privilege escalation from this vulnerability.
Mitigation Recommendations
Upgrade rabbitmq-server to version 3.13.15, 4.0.20, 4.1.11, 4.2.6, or later where this issue is fixed. No other mitigation is indicated or required as the fix addresses the root cause.
CVE-2026-66074: CWE-1333: Inefficient Regular Expression Complexity in rabbitmq rabbitmq-server
Description
CVE-2026-66074 is a vulnerability in rabbitmq-server where inefficient regular expression handling in the management API can cause excessive CPU consumption. The issue occurs when user-supplied regular expressions are executed repeatedly without a match limit, leading to high CPU usage especially with large resource sets. This can result in long processing times and scheduler saturation. The vulnerability affects versions prior to 3.13.15, 4.0.20, 4.1.11, and 4.2.6. It requires a user with the management tag to exploit. The issue has been fixed in the specified versions.
CVSS v4.0
Score 6.0medium
Affected software
rabbitmq
rabbitmq-server
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
RabbitMQ's management API allows users with the management tag to supply regular expressions via the ?name= parameter, which are passed to the Erlang re:run function without a match_limit option. Because the regex is executed once per resource in the result set, large numbers of resources (e.g., 5000 queues) can cause cumulative CPU consumption of many minutes per request. This inefficient regular expression complexity leads to potential denial of service by saturating CPU schedulers. The vulnerability is fixed in versions 3.13.15, 4.0.20, 4.1.11, and 4.2.6.
Potential Impact
An attacker with management tag privileges can cause high CPU usage on the RabbitMQ server by submitting crafted regular expressions that are executed repeatedly across many resources. This can degrade server performance and potentially lead to denial of service conditions due to scheduler saturation. There is no indication of data compromise or privilege escalation from this vulnerability.
Mitigation Recommendations
Upgrade rabbitmq-server to version 3.13.15, 4.0.20, 4.1.11, 4.2.6, or later where this issue is fixed. No other mitigation is indicated or required as the fix addresses the root cause.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-23T23:25:28.897Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab48379f7a7c54106b23c9e
Added to database: 09/24/2026, 01:57:13 UTC
Last enriched: 09/24/2026, 01:58:24 UTC
Last updated: 09/24/2026, 02:08:15 UTC
Views: 3
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