{"id":"CVE-2026-67235","summary":"RabbitMQ: AMQP 0-9-1 body assembly never validates accumulated size","details":"RabbitMQ is a messaging and streaming broker. Prior to versions 4.3.0, 4.2.6, 4.1.11, 4.0.20, and 3.13.15, The content-header BodySize (a uint64) was stored without validation against max_message_size. The size check ran only when assembly completed. By declaring body_size = 2^63-1 and then streaming fragments, a client ensured that check_msg_size never fired, so the accumulated body size went unbounded. A reader process accumulates memory until the memory alarm fires, degrading all publishers cluster-wide, or until the node runs out of memory. The memory alarm provides only partial mitigation, since it is reactive rather than preventive. AMQP 0-9-1 is the most widely used protocol, and any publisher can trigger this condition. Preconditions include Any authenticated AMQP 0-9-1 client with publish permission can exploit this.. This issue is fixed in versions 4.3.0, 4.2.6, 4.1.11, 4.0.20, and 3.13.15.","aliases":["GHSA-q8g2-pc7m-m3jw"],"modified":"2026-09-24T11:45:21.017560888Z","published":"2026-09-23T20:36:37.508Z","database_specific":{"cwe_ids":["CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67235.json","unresolved_ranges":[{"extracted_events":[{"introduced":"4.1.0"},{"fixed":"4.1.11"},{"introduced":"4.0.0"},{"fixed":"4.0.20"},{"introduced":"3.13.0"},{"fixed":"3.13.15"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67235.json"},{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6"},{"type":"WEB","url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0"},{"type":"ADVISORY","url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q8g2-pc7m-m3jw"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-67235"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/rabbitmq/rabbitmq-server","events":[{"introduced":"95c501fbad76c66156346cf364d158d6e30aa4d9"},{"fixed":"8a56c37f099a7bf609a555de3f0ff8ed23964d20"}],"database_specific":{"extracted_events":[{"introduced":"4.2.0"},{"fixed":"4.2.6"}],"source":"AFFECTED_FIELD"}}],"versions":["v4.2.5","v4.2.4","v4.2.3","v4.2.2","v4.2.1","v4.2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-67235.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}