CVE-2026-44431CWE-200

urllib3: Sensitive headers forwarded across origins in proxied low-level redirects

High · published May 13, 2026

CVSS v4.0
8.2
EPSS
0%
Percentile
26.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
8.2 · HIGH
Vector
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
EPSS
0.00339 · 26.2th percentile
Weakness
CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
Published
2026-05-13T15:20Z
EPSS history
Timeline
  • 13 MAY 15:20Z
    urllib3: Sensitive headers forwarded across origins in proxied low-level redirects
    cvelistv5