{"id":"CVE-2026-67219","state":"PUBLISHED","title":"RabbitMQ: Consistent-hash exchange unbounded weight","description":"RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_binding/3 parses the routing key as an integer weight N and computes ring positions with lists:seq(NextN0, NextN0 + N - 1). validate_binding/2 only checks N >= 1 , no upper bound. The resulting list is stored in the exchange's Khepri record, replicated cluster-wide, and reloaded on restart. A user with write permission on a consistent-hash exchange and read on a queue can create a binding whose routing key (the hash-ring weight) is an arbitrarily large integer. The broker allocates a list of that many integers via lists:seq/2 and persists it to Khepri across all cluster nodes , a single binding with weight 100000000 allocates ~800 MB on every node and survives restarts. Preconditions include rabbitmq_consistent_hash_exchange plugin enabled write permission on a consistent-hash exchange + read on a queue (standard binding perms). This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0.","publishedAt":"2026-09-23T20:38:42.653Z","updatedAt":"2026-09-24T14:20:08.627Z","severity":{"score":6,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["rabbitmq rabbitmq-server"],"affected":[{"vendor":"rabbitmq","product":"rabbitmq-server","versions":[{"version":">= 3.13.0, < 3.13.15","status":"affected"},{"version":">= 4.0.0, < 4.0.20","status":"affected"},{"version":">= 4.1.0, < 4.1.11","status":"affected"},{"version":">= 4.2.0, < 4.2.6","status":"affected"}]}],"references":["https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-m8pg-4x2h-jvgr","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6","https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0"],"weaknesses":["CWE-770"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/67xxx/CVE-2026-67219.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-67219","state":"PUBLISHED","datePublished":"2026-09-23T20:38:42.653Z","dateUpdated":"2026-09-24T14:20:08.627Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-28T19:50:39.437Z"},"containers":{"cna":{"title":"RabbitMQ: Consistent-hash exchange unbounded weight","descriptions":[{"lang":"en","value":"RabbitMQ is a messaging and streaming broker. Prior to versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0, add_binding/3 parses the routing key as an integer weight N and computes ring positions with lists:seq(NextN0, NextN0 + N - 1). validate_binding/2 only checks N >= 1 , no upper bound. The resulting list is stored in the exchange's Khepri record, replicated cluster-wide, and reloaded on restart. A user with write permission on a consistent-hash exchange and read on a queue can create a binding whose routing key (the hash-ring weight) is an arbitrarily large integer. The broker allocates a list of that many integers via lists:seq/2 and persists it to Khepri across all cluster nodes , a single binding with weight 100000000 allocates ~800 MB on every node and survives restarts. Preconditions include rabbitmq_consistent_hash_exchange plugin enabled write permission on a consistent-hash exchange + read on a queue (standard binding perms). This issue is fixed in versions 3.13.15, 4.0.20, 4.1.11, 4.2.6, and 4.3.0."}],"affected":[{"vendor":"rabbitmq","product":"rabbitmq-server","versions":[{"version":">= 3.13.0, < 3.13.15","status":"affected"},{"version":">= 4.0.0, < 4.0.20","status":"affected"},{"version":">= 4.1.0, < 4.1.11","status":"affected"},{"version":">= 4.2.0, < 4.2.6","status":"affected"}]}],"references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-m8pg-4x2h-jvgr","name":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-m8pg-4x2h-jvgr","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6","name":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6","tags":["x_refsource_MISC"]},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0","name":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV4_0":{"attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"PRESENT","privilegesRequired":"LOW","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"HIGH","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6,"baseSeverity":"MEDIUM","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-09-23T20:38:42.653Z"},"source":{"advisory":"GHSA-m8pg-4x2h-jvgr","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-24T14:19:46.502402Z","id":"CVE-2026-67219","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-24T14:20:08.627Z"}}]}}}