VulnerabilityModified

CVE-2026-44431

This vulnerability is fixed in 2.7.0.

HIGH 8.2EPSS 0.33%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.33%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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 4.0: 8.2 HIGHCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.33% probability · 26th percentile
CISA KEV: Not listed
Weakness: CWE-200
Affected: python/urllib3
Source: security-advisories@github.com

References

https://github.com/urllib3/urllib3/security/advisories/GHSA-qccp-gfcp-xxvcMitigation, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2026/06/msg00040.html

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.