{"id":"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.","aliases":["GHSA-8xx6-hgc6-gc2m"],"modified":"2026-09-05T03:30:42.492117557Z","published":"2026-09-02T18:03:05.010Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-409"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84382.json"},"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"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/pydantic/httpx2","events":[{"introduced":"0"},{"fixed":"4fd0c70a3f207c618b145934792f791bccfb39f8"},{"fixed":"71ae23be5448f859c2b4e21d9972ddfa7b8d759d"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"2.12.0"}]}}],"versions":["v2.11.0","v2.10.0","v2.9.1","v2.9.0","v2.8.0","v2.7.0","v2.6.0","v2.5.0","v2.4.0","v2.3.0","v2.2.0","v2.1.0","v2.0.0","v2.0.0b1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-84382.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}