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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v3.1
Weakness Type (CWE)
Vulnerable Products
pydantic:httpx2
References 4
https://github.com/pydantic/httpx2/commit/4fd0c70a3f207c618b145934792f791bccfb3…
security-advisories@github.com
https://github.com/pydantic/httpx2/pull/1126
security-advisories@github.com
https://github.com/pydantic/httpx2/releases/tag/v2.12.0
security-advisories@github.com
https://github.com/pydantic/httpx2/security/advisories/GHSA-8xx6-hgc6-gc2m
security-advisories@github.com