CVE-2026-44432
Last modified
CVE-2026-44432 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. urllib3 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). EPSS estimates a 0.68% chance of exploitation in the next 30 days.
Description
urllib3 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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Python | Urllib3 | >= 2.6.0, < 2.7.0 |
References
- https://github.com/urllib3/urllib3/security/advisories/GHSA-mf9v-mfxr-j63jMitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is CVE-2026-44432?
How severe is CVE-2026-44432?
How do I fix CVE-2026-44432?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-44427The MCP Registry provides MCP clients with a list of MCP ser…0
- CVE-2026-44428The MCP Registry provides MCP clients with a list of MCP ser…4.7
- CVE-2026-44429The MCP Registry provides MCP clients with a list of MCP ser…5.4
- CVE-2026-4443Heap buffer overflow in WebAudio in Google Chrome prior to 1…8.8
- CVE-2026-44430The MCP Registry provides MCP clients with a list of MCP ser…4
- CVE-2026-44431urllib3 is an HTTP client library for Python. From 1.23 to b…5.3
- CVE-2026-44433Quicly is an IETF QUIC protocol implementation intended prim…7.5
- CVE-2026-44434Quicly is an IETF QUIC protocol implementation intended prim…5.3
- CVE-2026-44435Quicly is an IETF QUIC protocol implementation intended prim…7.5
- CVE-2026-44436Quicly is an IETF QUIC protocol implementation intended prim…7.5
- CVE-2026-44437The Angular SSR is a server-rise rendering tool for Angular …6.1
- CVE-2026-44439PlaywrightCapture is a simple replacement for splash using p…7.5
Are you affected by CVE-2026-44432?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
