CVE-2026-84382 (GCVE-0-2026-84382)

Vulnerability from cvelistv5 – Published: 2026-09-02 18:03 – Updated: 2026-09-03 14:31
VLAI
Title
HTTPX2: Streaming response decompression does not bound peak memory (decompression amplification)
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-03 14:09 UTC
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7770 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
pydantic httpx2 Affected: < 2.12.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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