RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, pattern_to_regex maps % -> .*? and _ -> ., then compiles ^...$ with only [unicode]; re:run is called with only [{capture, none}] - no explicit match_limit. A pattern like %_%_..._%X becomes ^.*?..*?.....*?.X$ with overlapping lazy quantifiers. The whole-expression cap is ?MAX_EXPRESSION_LENGTH=4096 chars / ?MAX_TOKENS=200; a LIKE string literal is one token, so ~2000 %_ pairs fit. SQL filters are accepted unconditionally at rabbit_amqp_session.erl:3264 (no feature flag). Evaluated per-message at rabbit_stream_queue.erl:1439. OTP's default 10M match_limit caps each match at ~100-200 ms (not seconds), and the re NIF yields to the scheduler. An authenticated AMQP 1.0 consumer with read+write on a stream queue can cause ~100-200 ms of CPU per delivered message via a crafted LIKE filter, multiplied across thousands of messages and parallel sessions - a substantial backtracking-driven CPU amplification. Preconditions include AMQP 1.0 with stream queues in use Attacker can attach a receiver with a filter (read permission) and publish messages with long property values (write permission). This issue is fixed in versions 4.2.7 and 4.3.1.

rabbitmq-server: RabbitMQ: Unsanitized vhost names allow for XSS in management UI rabbitmq: RabbitMQ: Authenticated user can bypass connection limits via stream protocol rabbitmq: RabbitMQ: Information disclosure of decrypted Shovel URIs in debug logs rabbitmq-server: RabbitMQ: Monitoring user can reset authentication attempt counters rabbitmq-server: RabbitMQ: Cross-Origin Resource Sharing (CORS) misconfiguration allows unauthorized actions rabbitmq-server: RabbitMQ: Denial of Service via atom table exhaustion in stream chunk_selector rabbitmq: RabbitMQ: Denial of Service via management API regular expression filter rabbitmq-server: RabbitMQ: Monitoring user can disrupt message flow via authorization flaw rabbitmq: RabbitMQ: Information disclosure via cross-vhost authorization bypass RabbitMQ: RabbitMQ: Account takeover via stored Cross-Site Scripting in TLS peer-certificate DN rabbitmq-server: RabbitMQ: Denial of Service via AMQP 1.0 array32 parsing rabbitmq-server: RabbitMQ: Denial of Service via unbounded super-stream partition allocation rabbitmq-server: RabbitMQ: Privilege escalation via super-stream HTTP creation rabbitmq: RabbitMQ: Denial of Service via unbounded consistent-hash exchange weight rabbitmq-server: RabbitMQ: Denial of Service via JMS topic exchange atom exhaustion rabbitmq: RabbitMQ: Information disclosure of AMQP 1.0 shovel URI passwords rabbitmq: RabbitMQ: Administrator path traversal allows arbitrary file write rabbitmq: RabbitMQ: Denial of Service vi…

Affected: Ubuntu:Pro:16.04:LTS: rabbitmq-server, Ubuntu:18.04:LTS: rabbitmq-server, Ubuntu:20.04:LTS: rabbitmq-server, Ubuntu:22.04:LTS: rabbitmq-server, Ubuntu:24.04:LTS: rabbitmq-server, Ubuntu:26.04:LTS: rabbitmq-server

RabbitMQ is a messaging and streaming broker. Prior to versions 4.2.7 and 4.3.1, pattern_to_regex maps % -> .*? and _ -> ., then compiles ^...$ with only [unicode]; re:run is called with only [{capture, none}] - no explicit match_limit. A pattern like %_%_..._%X becomes ^.*?..*?.....*?.X$ with overlapping lazy quantifiers. The whole-expression cap is ?MAX_EXPRESSION_LENGTH=4096 chars / ?MAX_TOKENS=200; a LIKE string literal is one token, so ~2000 %_ pairs fit. SQL filters are accepted unconditionally at rabbit_amqp_session.erl:3264 (no feature flag). Evaluated per-message at rabbit_stream_queue.erl:1439. OTP's default 10M match_limit caps each match at ~100-200 ms (not seconds), and the re NIF yields to the scheduler. An authenticated AMQP 1.0 consumer with read+write on a stream queue can cause ~100-200 ms of CPU per delivered message via a crafted LIKE filter, multiplied across thousands of messages and parallel sessions - a substantial backtracking-driven CPU amplification. Preconditions include AMQP 1.0 with stream queues in use Attacker can attach a receiver with a filter (read permission) and publish messages with long property values (write permission). This issue is fixed in versions 4.2.7 and 4.3.1.