{"id":"CVE-2026-67240","state":"PUBLISHED","title":"RabbitMQ: ReDoS via AMQP 1.0 SQL filter LIKE wildcard","description":"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.","publishedAt":"2026-09-23T20:19:22.703Z","updatedAt":"2026-09-24T14:24:51.504Z","severity":{"score":2.3,"label":"Low","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["rabbitmq rabbitmq-server"],"affected":[{"vendor":"rabbitmq","product":"rabbitmq-server","versions":[{"version":">= 4.2.0, < 4.2.7","status":"affected"},{"version":">= 4.3.0, < 4.3.1","status":"affected"}]}],"references":["https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-59c5-553c-57m2","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1"],"weaknesses":["CWE-1333"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/67xxx/CVE-2026-67240.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-67240","state":"PUBLISHED","datePublished":"2026-09-23T20:19:22.703Z","dateUpdated":"2026-09-24T14:24:51.504Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-28T19:50:39.438Z"},"containers":{"cna":{"title":"RabbitMQ: ReDoS via AMQP 1.0 SQL filter LIKE wildcard","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"rabbitmq","product":"rabbitmq-server","versions":[{"version":">= 4.2.0, < 4.2.7","status":"affected"},{"version":">= 4.3.0, < 4.3.1","status":"affected"}]}],"references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-59c5-553c-57m2","name":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-59c5-553c-57m2","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7","name":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.7","tags":["x_refsource_MISC"]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1","name":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":2.3,"baseSeverity":"LOW","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-23T20:19:22.703Z"},"source":{"advisory":"GHSA-59c5-553c-57m2","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-59c5-553c-57m2","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-24T14:24:20.497820Z","id":"CVE-2026-67240","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-24T14:24:51.504Z"}}]}}}