{"id":"CVE-2026-67235","title":"RabbitMQ is a messaging and streaming broker","summary":"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 assemb…","severity":"high","cvss":7.1,"cvssVector":"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","cwe":["CWE-770"],"vendor":"rabbitmq","product":"rabbitmq-server","affected":["rabbitmq-server >= 4.2.0, < 4.2.6","rabbitmq-server >= 4.1.0, < 4.1.11","rabbitmq-server >= 4.0.0, < 4.0.20","rabbitmq-server >= 3.13.0, < 3.13.15"],"published":"2026-09-23","updated":"2026-09-23","sourceUpdated":"2026-09-23T21:17:01.227","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-67235","references":[{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.2.6","label":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/releases/tag/v4.3.0","label":"security-advisories@github.com"},{"url":"https://github.com/rabbitmq/rabbitmq-server/security/advisories/GHSA-q8g2-pc7m-m3jw","label":"security-advisories@github.com"}],"tags":["nvd","cve.org"],"cvssSource":"cna","ingestedAt":"2026-09-23T21:33:13.531Z","slug":"CVE-2026-67235","body":"## Overview\n\nRabbitMQ 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}