{"id":"CVE-2026-82672","summary":"Unvalidated chunk-size line tail in Mint HTTP/1 client enables response smuggling against strict intermediaries on pooled connections","details":"Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in elixir-mint mint allows a malicious HTTP/1 server to desynchronize a strict intermediary and the Mint client on a pooled connection, enabling response-queue poisoning against subsequent requests that share the connection.\n\nMint.HTTP1.Parse.chunk_size/1 in lib/mint/http1/parse.ex stops at the first non-hexadecimal byte of a chunked response's chunk-size line and returns the remainder unexamined. Mint.HTTP1.decode_body/5 in lib/mint/http1.ex then discards every byte up to the CRLF with Parse.ignore_until_crlf/1, so the accepted grammar is a run of hex digits followed by arbitrary bytes, where RFC 9112 permits only a ;-introduced chunk extension. Lines such as 5ZZZZZ and 5 9 are accepted as chunk size 5, and 0ZZZZ is accepted as the terminating chunk that ends the message body. An RFC-strict intermediary rejects such a line while Mint accepts it, so the two disagree on chunk boundaries and on where the response ends.\n\nThis issue affects mint: from 0.1.0 before 1.10.1.","aliases":["EEF-CVE-2026-82672","GHSA-rj5m-69wp-cxq9"],"modified":"2026-09-23T03:30:27.635157806Z","published":"2026-09-19T17:00:31.648Z","database_specific":{"unresolved_ranges":[{"extracted_events":[{"introduced":"60089586ec7adc9fddb09f69a2f5919ba9ac7f33"},{"fixed":"c82377838dc6e275ef40bafa664fbcdf50270c60"}],"source":"AFFECTED_FIELD"}],"cna_assigner":"EEF","cwe_ids":["CWE-444"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82672.json"},"references":[{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-82672.html"},{"type":"WEB","url":"https://github.com"},{"type":"WEB","url":"https://osv.dev/vulnerability/EEF-CVE-2026-82672"},{"type":"WEB","url":"https://repo.hex.pm"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/82xxx/CVE-2026-82672.json"},{"type":"ADVISORY","url":"https://github.com/elixir-mint/mint/security/advisories/GHSA-rj5m-69wp-cxq9"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82672"},{"type":"FIX","url":"https://github.com/elixir-mint/mint/commit/60089586ec7adc9fddb09f69a2f5919ba9ac7f33"},{"type":"FIX","url":"https://github.com/elixir-mint/mint/commit/c82377838dc6e275ef40bafa664fbcdf50270c60"},{"type":"PACKAGE","url":"https://github.com/elixir-mint/mint"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/elixir-mint/mint","events":[{"introduced":"47889857fb36f07606ad9c2e52080d202d419058"},{"fixed":"9e9ae10cb6321879b8cf74dea3dd3e91d0e72f41"},{"fixed":"60089586ec7adc9fddb09f69a2f5919ba9ac7f33"},{"fixed":"c82377838dc6e275ef40bafa664fbcdf50270c60"}],"database_specific":{"extracted_events":[{"introduced":"0.1.0"},{"fixed":"1.10.1"}],"source":["DESCRIPTION","REFERENCES"]}}],"versions":["v1.10.0","v1.9.3","v1.9.2","v1.9.1","v1.9.0","v1.8.0","v1.7.1","v1.7.0","v1.6.2","v1.6.1","v1.6.0","v1.5.2","v1.5.1","v1.5.0","v1.4.2","v1.4.1","v1.4.0","v1.3.0","v1.2.1","v1.2.0","v1.1.0","v1.0.0","v0.5.0","v0.4.0","v0.2.1","v0.2.0","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-82672.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"}]}