{"id":"CVE-2026-47077","summary":"Unbounded body accumulation in HTTP/3 response loop in hackney","details":"Allocation of Resources Without Limits or Throttling vulnerability in benoitc hackney allows Flooding. hackney_h3:await_response_loop/6 accumulates the HTTP/3 response body in memory without any size cap. The after Timeout clause is a per-message inactivity timer that resets on every received chunk, housekeeping message, or settings frame — it is not a wall-clock deadline. A malicious HTTP/3 server that emits one small chunk every Timeout - 1 ms with Fin = false and never sends a final frame keeps the loop alive indefinitely while the accumulation buffer grows linearly without bound, eventually exhausting the BEAM process heap and causing an out-of-memory condition.\n\nThis issue affects hackney: from 2.0.0 before 4.0.1.","aliases":["EEF-CVE-2026-47077","GHSA-jq4m-q6p2-8gwc"],"modified":"2026-07-08T08:13:37.111547123Z","published":"2026-05-25T14:00:42.217Z","database_specific":{"cwe_ids":["CWE-400"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47077.json","unresolved_ranges":[{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0334af206d5099fdf510ed9eda18e34396f065ad"},{"fixed":"3d25f9fea26c90609de9d64366fedfe5065413bc"}]}],"cna_assigner":"EEF"},"references":[{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-47077.html"},{"type":"WEB","url":"https://github.com"},{"type":"WEB","url":"https://osv.dev/vulnerability/EEF-CVE-2026-47077"},{"type":"WEB","url":"https://repo.hex.pm"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/47xxx/CVE-2026-47077.json"},{"type":"ADVISORY","url":"https://github.com/benoitc/hackney/security/advisories/GHSA-jq4m-q6p2-8gwc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-47077"},{"type":"FIX","url":"https://github.com/benoitc/hackney/commit/3d25f9fea26c90609de9d64366fedfe5065413bc"},{"type":"PACKAGE","url":"https://github.com/benoitc/hackney"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/benoitc/hackney","events":[{"introduced":"a7ce34b42892ab305b2ef7dbe873bcabf4ef93ca"},{"fixed":"c41c8d48ace8141b003f6f1de3ca6734a0c53056"},{"fixed":"3d25f9fea26c90609de9d64366fedfe5065413bc"}],"database_specific":{"cpe":"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"2.0.0"},{"fixed":"4.0.1"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["4.0.0","3.2.1","3.2.0","3.1.2","3.1.1","3.1.0","3.0.3","3.0.2","3.0.1","2.0.1","2.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-47077.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}