23 Oct 2026 15:48:27 UTC
urllib3: Decompression-bomb safeguards bypassed in parts of the streaming API
cve-program · CVE-2026-44432 · Published
CVE-2026-44432
urllib3: Decompression-bomb safeguards bypassed in parts of the streaming API
CVSS 4.0 8.9 HIGHCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-44432
Publishedurllib3 is an HTTP client library for Python. From 2.6.0 to before 2.7.0, urllib3 could decompress the whole response instead of the requested portion (1) during the second HTTPResponse.read(amt=N) call when the response was decompressed using the official Brotli library or (2) when HTTPResponse.drain_conn() was called after the response had been read and decompressed partially (compression algorithm did not matter here). These issues could cause urllib3 to fully decode a small amount of highly compressed data in a single operation. This could result in excessive resource consumption (high CPU usage and massive memory allocation for the decompressed data) on the client side. This vulnerability is fixed in 2.7.0.
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