{"id":"CVE-2026-47077","aliases":["EEF-CVE-2026-47077","GHSA-jq4m-q6p2-8gwc"],"url":"https://o3.security/vulnerability/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.","published":"2026-05-25T14:00:42.217Z","modified":"2026-08-12T03:51:19.894156098Z","cvss":null,"epss":{"score":0.00703,"percentile":0.51016,"asOf":"2026-09-08"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Hex","name":"hackney","fixedVersion":"4.0.1"}],"fix":{"url":"https://github.com/benoitc/hackney/commit/3d25f9fea26c90609de9d64366fedfe5065413bc","label":"benoitc/hackney@3d25f9f"},"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"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:19.894156098Z"}}