Cross-Origin Redirect Issue in urllib3 HTTP Client Library
CVE-2026-44431

8.2HIGH

Key Information:

Vendor

Urllib3

Status
Urllib3
Vendor
CVE Published:
13 May 2026

What is CVE-2026-44431?

The urllib3 HTTP client library for Python contains a cross-origin redirect vulnerability that affects versions 1.23 up to 2.7.0. When using the low-level API through ProxyManager.connection_from_url(), if assert_same_host is set to False, sensitive headers may inadvertently be forwarded during cross-origin redirects. This issue can lead to unintended exposure of user data. Users are advised to upgrade to version 2.7.0 or later to mitigate this risk.

Affected Version(s)

urllib3 >= 1.23, < 2.7.0

References

https://github.com/urllib3/urllib3/security/advisories/GH...
x_refsource_CONFIRM

CVSS V4

Score:
8.2
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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