{"id":"CVE-2026-84382","aliases":["GHSA-8xx6-hgc6-gc2m"],"url":"https://o3.security/vulnerability/CVE-2026-84382","summary":"HTTPX2: Streaming response decompression does not bound peak memory (decompression amplification)","details":"HTTPX2 is a next generation HTTP client for Python. Prior to 2.12.0, the HTTPX2 content decoders in src/httpx2/httpx2/_decoders.py fully inflate each gzip, deflate, br, or zstd network chunk before iter_bytes() or aiter_bytes() yields bounded pieces to the application. A 64 KiB compressed chunk can expand to approximately 64 MiB in one intermediate allocation, so an attacker-controlled or compromised server can cause severe memory pressure or out-of-memory process termination even when the application streams the response. This issue is fixed in version 2.12.0.","published":"2026-09-02T18:03:05.010Z","modified":"2026-09-04T03:47:29.217778969Z","cvss":{"score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[],"fix":{"url":"https://github.com/pydantic/httpx2/commit/4fd0c70a3f207c618b145934792f791bccfb39f8","label":"pydantic/httpx2@4fd0c70"},"references":[{"type":"WEB","url":"https://github.com/pydantic/httpx2/releases/tag/v2.12.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84382.json"},{"type":"ADVISORY","url":"https://github.com/pydantic/httpx2/security/advisories/GHSA-8xx6-hgc6-gc2m"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-84382"},{"type":"FIX","url":"https://github.com/pydantic/httpx2/commit/4fd0c70a3f207c618b145934792f791bccfb39f8"},{"type":"FIX","url":"https://github.com/pydantic/httpx2/pull/1126"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-09-04T03:47:29.217778969Z"}}