{"id":"CVE-2026-44236","summary":"rabbitmq-c: Heap buffer overflow in AMQP login handshake via undersized connection.tune.frame_max","details":"rabbitmq-c is a C-language AMQP client library for RabbitMQ. Prior to 0.16.0, a malicious AMQP server can send an undersized connection.tune.frame_max value during amqp_login(), and rabbitmq-c accepts the value in amqp_login_inner() in librabbitmq/amqp_socket.c. amqp_tune_connection() in librabbitmq/amqp_connection.c uses frame_max to reallocate the outbound buffer without enforcing AMQP_FRAME_MIN_SIZE. Immediate serialization of connection.tune-ok through amqp_frame_to_bytes() writes beyond the undersized heap allocation, causing memory corruption and likely denial of service. An on-path attacker can also trigger the flaw against plaintext AMQP traffic. Code execution is theoretically possible but was not demonstrated. This issue is fixed in version 0.16.0.","aliases":["GHSA-jh48-qjf5-fx5v"],"modified":"2026-09-19T08:35:41.215950Z","published":"2026-09-17T17:04:18.803Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-122"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44236.json"},"references":[{"type":"WEB","url":"https://github.com/alanxz/rabbitmq-c/releases/tag/v0.16.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44236.json"},{"type":"ADVISORY","url":"https://github.com/alanxz/rabbitmq-c/security/advisories/GHSA-jh48-qjf5-fx5v"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-44236"},{"type":"FIX","url":"https://github.com/alanxz/rabbitmq-c/commit/4777d0b5c58cb02966a04a85832436bd66ed5d1f"},{"type":"FIX","url":"https://github.com/alanxz/rabbitmq-c/pull/879"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/alanxz/rabbitmq-c","events":[{"introduced":"0"},{"fixed":"4777d0b5c58cb02966a04a85832436bd66ed5d1f"},{"fixed":"800d57c9ca7352181167ec3c6aba66b8518c321c"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"0.16.0"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v0.15.0","v0.14.0","v0.13.0","v0.12.0","v0.11.0","v0.10.0","v0.9.0-master","v0.8.0","v0.7.1","v0.7.0","v0.6.0","v0.5.2","v0.5.1","v0.5.0","v0.4.0","v0.4.0-test","v0.3.0","rabbitmq-c-v0.3.0","v0.2","0.2","v0.1","librabbitmq-0.1-amqp_0_8"],"database_specific":{"vanir_signatures_modified":"2026-09-19T08:35:41Z","vanir_signatures":[{"signature_version":"v1","source":"https://github.com/alanxz/rabbitmq-c/commit/4777d0b5c58cb02966a04a85832436bd66ed5d1f","target":{"file":"librabbitmq/amqp_connection.c"},"deprecated":false,"digest":{"line_hashes":["56805020904733202547779373711471559129","288170581025835855161700820896167262557","287080036094929802673770365321867277486"],"threshold":0.9},"id":"CVE-2026-44236-38b4e732","signature_type":"Line"},{"target":{"file":"librabbitmq/amqp_socket.c"},"deprecated":false,"digest":{"line_hashes":["9339284196412423178463322050873005001","222086157520034534071065244646110944265","321170672453905414205851976788382851471","264074435893008367961083926954424315035"],"threshold":0.9},"id":"CVE-2026-44236-6d02f414","signature_type":"Line","signature_version":"v1","source":"https://github.com/alanxz/rabbitmq-c/commit/4777d0b5c58cb02966a04a85832436bd66ed5d1f"},{"source":"https://github.com/alanxz/rabbitmq-c/commit/4777d0b5c58cb02966a04a85832436bd66ed5d1f","target":{"function":"amqp_tune_connection","file":"librabbitmq/amqp_connection.c"},"deprecated":false,"digest":{"function_hash":"89562769440926694974221019230632344268","length":733},"id":"CVE-2026-44236-a8d32cfc","signature_type":"Function","signature_version":"v1"},{"id":"CVE-2026-44236-ab10a181","signature_type":"Function","signature_version":"v1","source":"https://github.com/alanxz/rabbitmq-c/commit/4777d0b5c58cb02966a04a85832436bd66ed5d1f","target":{"file":"librabbitmq/amqp_socket.c","function":"amqp_login_inner"},"deprecated":false,"digest":{"function_hash":"333562871886587755336192254291593491910","length":4335}}],"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-44236.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:H"}]}