CVE-2026-44431

urllib3 is an HTTP client library for Python. From 1.23 to before 2.7.0, cross-origin redirects followed from the low-level API via ProxyManager.connection_from_url().urlopen(..., assert_same_host=False) still forward these sensitive headers. This vulnerability is fixed in 2.7.0.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvc	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:python:urllib3:*:*:*:*:*:*:*:*

History

14 May 2026, 13:56

Type	Values Removed	Values Added
References	~~() https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvc -~~	() https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvc - Mitigation, Vendor Advisory
CWE		NVD-CWE-noinfo
First Time		Python Python urllib3
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
CPE		cpe:2.3:a:python:urllib3::::::::

13 May 2026, 17:06

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 16:16

Updated : 2026-05-14 13:56

NVD link : CVE-2026-44431

Mitre link : CVE-2026-44431

CVE.ORG link : CVE-2026-44431

JSON object : View

Products Affected

python

urllib3

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

NVD-CWE-noinfo

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