Skip to content
Fencer Intel
medium 5.3

CVE-2026-44431 json

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

published 5mo ago modified last mo. also EUVD-2026-30046 , GHSA-qccp-gfcp-xxvc , PYSEC-2026-141

cvss
5.3
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 26%
public exploits
0
none known

Summary

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.

Patch / fix

  • pypi urllib3 2.7.0
  • python urllib3 2.7.0
  • python-urllib3 Debian 12 1.26.12-1+deb12u4
  • python-urllib3 Debian 13 2.3.0-3+deb13u2
  • python-urllib3 Debian 14 2.7.0-1

debian advisories DEBIAN-CVE-2026-44431

  • python-urllib3 Ubuntu 22.04 LTS 1.26.5-1~exp1ubuntu0.7
  • python-urllib3 Ubuntu 24.04 LTS 2.0.7-1ubuntu0.7
  • python-urllib3 Ubuntu 25.10 2.3.0-3ubuntu0.6
  • python-urllib3 Ubuntu 26.04 LTS 2.6.3-1ubuntu1.1
  • python-urllib3 Ubuntu Pro 16.04 LTS 1.13.1-2ubuntu0.16.04.4+esm4
  • python-urllib3 Ubuntu Pro 18.04 LTS 1.22-1ubuntu0.18.04.2+esm4
  • python-urllib3 Ubuntu Pro 20.04 LTS 1.25.8-2ubuntu0.4+esm5

ubuntu advisories UBUNTU-CVE-2026-44431

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • resource-agents RHEL 8 4.9.0-54.el8_10.36
  • resource-agents-gcp RHEL 8 4.9.0-54.el8_10.36
  • resource-agents-paf RHEL 8 4.9.0-54.el8_10.36
  • resource-agents-aliyun RHEL 8 4.9.0-54.el8_10.36
  • fence-agents RHEL 8 4.2.1-129.el8_10.28
  • fence-agents-all RHEL 8 4.2.1-129.el8_10.28
  • fence-agents-apc RHEL 8 4.2.1-129.el8_10.28
  • fence-agents-aws RHEL 8 4.2.1-129.el8_10.28

red hat advisories RHSA-2026:60371RHSA-2026:60362RHSA-2026:59409RHSA-2026:47129RHSA-2026:47126RHSA-2026:51157

  • grafana Multi Linux Manager Tools SLE-15 12.4.10-150002.4.27.1
  • mgr-push Multi Linux Manager Tools SLE-15 5.2.5-150002.3.12.1
  • spacecmd Multi Linux Manager Tools SLE-15 5.2.10-150002.3.15.1
  • uyuni-tools Multi Linux Manager Tools SLE-Micro-5, Multi Linux Manager Tools SLE-15 5.2.17-150002.3.20.1
  • venv-salt-minion Multi Linux Manager Tools SLE-Micro-5, Multi Linux Manager Tools SLE-15 3006.0-150002.5.22.1
  • spacewalk-client-tools Multi Linux Manager Tools SLE-15 5.2.7-150002.3.12.1
  • golang-github-prometheus-prometheus Multi Linux Manager Tools SLE-15 3.13.2-150002.3.19.1
  • mgr-push Multi Linux Manager Tools SLE-12 5.2.5-120002.3.12.1

suse advisories SUSE-SU-2026:4585-1SUSE-SU-2026:4584-1SUSE-SU-2026:4583-1SUSE-SU-2026:4582-1SUSE-SU-2026:4581-1SUSE-SU-2026:4580-1

  • python-urllib3_1 openSUSE Tumbleweed 1.26.20-6.1

opensuse advisories openSUSE-SU-2026:10838-1

  • fence-agents-all AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-apc AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-aws AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-eps AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-gce AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-rsa AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-rsb AlmaLinux 8 4.2.1-129.el8_10.28
  • fence-agents-sbd AlmaLinux 8 4.2.1-129.el8_10.28

almalinux advisories ALSA-2026:49927ALSA-2026:47126ALSA-2026:36732ALSA-2026:32992ALSA-2026:28157ALSA-2026:28158

  • resource-agents Rocky Linux 8 4.9.0-54.el8_10.36
  • fence-agents Rocky Linux 8 4.2.1-129.el8_10.28
  • python-urllib3 Rocky Linux 8 1.24.2-10.el8_10
  • python3.12-urllib3 Rocky Linux 8 1.26.19-3.el8_10
  • python-urllib3 Rocky Linux 10 1.26.19-4.el10_2
  • python3.14-urllib3 Rocky Linux 10 2.6.3-2.el10_2
  • python-urllib3 Rocky Linux 9 1.26.5-8.el9_8
  • python3.14-urllib3 Rocky Linux 9 2.6.3-2.el9_8

rocky linux advisories RLSA-2026:47126RLSA-2026:49927RLSA-2026:36732RLSA-2026:32992RLSA-2026:28000RLSA-2026:27929

  • python-urllib3 Azure Linux 3.0 2.0.7-5

azure linux advisories AZL-86862

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Is CVE-2026-44431 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-44431 updated cvss 5.9

urllib3: urllib3: Information disclosure via cross-origin redirects forwarding sensitive headers

  • Red Hat Exploit Intelligence exploit-intelligence-tech-preview/vulnerability-analysis-rhel9
    affected: no fix planned “Out of support scope”
  • Red Hat Migration Toolkit for Containers rhmtc/openshift-migration-rhel8-operator
    affected: no fix available
  • Red Hat Migration Toolkit for Virtualization mtv-candidate/mtv-rhel9-operator, migration-toolkit-virtualization/mtv-rhel9-operator
    affected: no fix available, no fix planned “Will not fix”
  • Red Hat OpenShift Lightspeed openshift-lightspeed/lightspeed-to-dataverse-exporter-rhel9
    affected: no fix available
  • Red Hat Pen Drive Powered by Red Hat Lightspeed pen-drive/pen-drive-scanner-rhel9 Red Hat AI Inference Server rhaiis/vllm-cpu-rhel9, rhaiis/vllm-tpu-rhel9, rhaiis/vllm-neuron-rhel9
    affected: no fix planned “Will not fix”
  • Red Hat Ansible Automation Platform 2 ansible-automation-platform-24/lightspeed-rhel8, ansible-automation-platform-25/lightspeed-rhel8, ansible-automation-platform-25/ee-supported-rhel8, ansible-automation-platform-26/ee-supported-rhel9, ansible-automation-platform-26/hub-rhel9-operator, ansible-automation-platform-26/eda-controller-rhel9, +9 more
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat Developer Hub 1 rhdh/rhdh-hub-rhel9 Red Hat Enterprise Linux 7 python-s3transfer
    affected: no fix planned “Will not fix”
  • Red Hat OpenShift AI (RHOAI) rhoai/rhai-cli-rhel9, rhoai/odh-vllm-gaudi-rhel9, rhoai/odh-openvino-model-server-rhel9, rhoai/odh-modelmesh-runtime-adapter-rhel8
    affected: no fix available, no fix planned “Out of support scope”
show 30 more
  • Red Hat OpenShift Container Platform 4 openshift4/ztp-site-generate-rhel8
    affected: no fix planned “Will not fix”
  • Red Hat OpenShift Virtualization 4 container-native-virtualization/hyperconverged-cluster-webhook-rhel9, container-native-virtualization/hyperconverged-cluster-operator-rhel9
    affected: no fix planned “Out of support scope”
  • Red Hat Quay 3 quay/quay-rhel8, quay/quay-rhel9
    affected: no fix available, no fix planned “Out of support scope”
  • Red Hat Trusted Artifact Signer rhtas/segment-reporting-rhel9
    affected: no fix planned “Out of support scope”
  • Red Hat AI Inference Server 3.2 rhaiis/vllm-cuda-rhel9 1790621718, rhaiis/vllm-rocm-rhel9 1790621713, rhaiis/model-opt-cuda-rhel9 1790621714
    fixed: vendor fix RHSA-2026:73859
  • Red Hat AI Inference Server 3.3 rhaiis/vllm-cuda-rhel9 1782352847, rhaiis/vllm-rocm-rhel9 1782353093, rhaiis/vllm-spyre-rhel9 1782352919, rhaiis/model-opt-cuda-rhel9 1782352950
    fixed: vendor fix RHSA-2026:30078
  • Red Hat AI Inference Server 3.4 rhaii/vllm-cpu-rhel9 1780356811, rhaii/vllm-cuda-rhel9 1780356914, rhaii/vllm-spyre-rhel9 1780356904, rhaii/model-opt-cuda-rhel9 1780356941
    fixed: vendor fix RHSA-2026:24542
  • Red Hat AI Inference Server 3.5 rhaii/vllm-cpu-rhel9 1791473614, rhaii/vllm-cuda-rhel9 1791473631, rhaii/vllm-rocm-rhel9 1791425869, rhaii/vllm-gaudi-rhel9 1791427182, rhaii/vllm-spyre-rhel9 1791818357, rhaii/model-opt-cuda-rhel9 1791803821
    fixed: vendor fix RHSA-2026:82066
  • Red Hat Ansible Automation Platform 2.5 ansible-automation-platform-25/hub-rhel8 1784050598
    fixed: vendor fix RHSA-2026:42144
  • Red Hat Ansible Automation Platform 2.6 ansible-automation-platform-26/gateway-rhel9 1782761510, ansible-automation-platform-26/controller-rhel9 1783973764, ansible-automation-platform-26/de-minimal-rhel9 1783921549, ansible-automation-platform-26/de-supported-rhel9 1783923629, ansible-automation-platform-26/lightspeed-chatbot-rhel9 1782650747, ansible-automation-platform-tech-preview/metrics-service-rhel9 1783969139
    fixed: vendor fix RHSA-2026:42132
  • Red Hat Ansible Automation Platform 2.6 for RHEL 9 python3.12-urllib3 2.7.0-1.el9ap
    fixed: vendor fix RHSA-2026:34160
  • Red Hat Ansible Automation Platform 2.7 ansible-automation-platform-27/hub-rhel9 1781102816
    fixed: vendor fix RHSA-2026:25928
  • Red Hat Discovery 2 discovery/discovery-ui-rhel9 1782756541
    fixed: vendor fix RHSA-2026:33313
  • Red Hat Enterprise Linux AI 3.5 rhelai3/bootc-cuda-rhel9 1793135861, rhelai3/bootc-rocm-rhel9 1793135863, rhelai3/bootc-aws-cuda-rhel9 1793194817, rhelai3/bootc-gcp-cuda-rhel9 1793194815, rhelai3/disk-image-cuda-rhel9 1793206758, rhelai3/bootc-azure-cuda-rhel9 1793194815, +1 more
    fixed: vendor fix RHSA-2026:92452
  • Red Hat Enterprise Linux AppStream (v. 8) fence-agents 4.2.1-129.el8_10.28, python3.12-urllib3 1.26.19-3.el8_10, fence-agents-all 4.2.1-129.el8_10.28, fence-agents-apc 4.2.1-129.el8_10.28, fence-agents-eps 4.2.1-129.el8_10.28, fence-agents-rsa 4.2.1-129.el8_10.28, +39 more
    fixed: vendor fix RHSA-2026:49927
  • Red Hat Enterprise Linux AppStream (v. 9) python3.14-urllib3 2.6.3-2.el9_8, python3.12-urllib3 1.26.19-3.el9_8
    fixed: vendor fix RHSA-2026:28159
  • Red Hat Enterprise Linux AppStream (v. 10) python3.14-urllib3 2.6.3-2.el10_2
    fixed: vendor fix RHSA-2026:27929
  • Red Hat Enterprise Linux AppStream AUS (v.8.4) fence-agents 4.2.1-65.el8_4.31, fence-agents-all 4.2.1-65.el8_4.31, fence-agents-apc 4.2.1-65.el8_4.31, fence-agents-eps 4.2.1-65.el8_4.31, fence-agents-rsa 4.2.1-65.el8_4.31, fence-agents-rsb 4.2.1-65.el8_4.31, +37 more
    fixed: vendor fix RHSA-2026:51152
  • Red Hat Enterprise Linux AppStream AUS (v.8.6) fence-agents 4.2.1-89.el8_6.25, fence-agents-all 4.2.1-89.el8_6.25, fence-agents-apc 4.2.1-89.el8_6.25, fence-agents-eps 4.2.1-89.el8_6.25, fence-agents-rsa 4.2.1-89.el8_6.25, fence-agents-rsb 4.2.1-89.el8_6.25, +37 more
    fixed: vendor fix RHSA-2026:51157
  • Red Hat Enterprise Linux AppStream E4S (v.8.8) fence-agents 4.2.1-112.el8_8.20, fence-agents-all 4.2.1-112.el8_8.20, fence-agents-apc 4.2.1-112.el8_8.20, fence-agents-eps 4.2.1-112.el8_8.20, fence-agents-rsa 4.2.1-112.el8_8.20, fence-agents-rsb 4.2.1-112.el8_8.20, +37 more
    fixed: vendor fix RHSA-2026:51045
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) fence-agents 4.2.1-65.el8_4.31, fence-agents-all 4.2.1-65.el8_4.31, fence-agents-apc 4.2.1-65.el8_4.31, fence-agents-eps 4.2.1-65.el8_4.31, fence-agents-rsa 4.2.1-65.el8_4.31, fence-agents-rsb 4.2.1-65.el8_4.31, +33 more
    fixed: vendor fix RHSA-2026:51152
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) fence-agents 4.2.1-89.el8_6.25, fence-agents-all 4.2.1-89.el8_6.25, fence-agents-apc 4.2.1-89.el8_6.25, fence-agents-eps 4.2.1-89.el8_6.25, fence-agents-rsa 4.2.1-89.el8_6.25, fence-agents-rsb 4.2.1-89.el8_6.25, +37 more
    fixed: vendor fix RHSA-2026:51157
  • Red Hat Enterprise Linux AppStream TUS (v.8.8) fence-agents 4.2.1-112.el8_8.20, fence-agents-all 4.2.1-112.el8_8.20, fence-agents-apc 4.2.1-112.el8_8.20, fence-agents-eps 4.2.1-112.el8_8.20, fence-agents-rsa 4.2.1-112.el8_8.20, fence-agents-rsb 4.2.1-112.el8_8.20, +36 more
    fixed: vendor fix RHSA-2026:51045
  • Red Hat Enterprise Linux BaseOS (v. 8) python-urllib3 1.24.2-10.el8_10, python3-urllib3 1.24.2-10.el8_10
    fixed: vendor fix RHSA-2026:36732
  • Red Hat Enterprise Linux BaseOS (v. 9) python-urllib3 1.26.5-8.el9_8, python3-urllib3 1.26.5-8.el9_8
    fixed: vendor fix RHSA-2026:28158
  • Red Hat Enterprise Linux BaseOS (v. 10) python-urllib3 1.26.19-4.el10_2, python3-urllib3 1.26.19-4.el10_2
    fixed: vendor fix RHSA-2026:28000
  • Red Hat Enterprise Linux BaseOS E4S (v.9.2) python-urllib3 1.26.5-3.el9_2.4, python3-urllib3 1.26.5-3.el9_2.4
    fixed: vendor fix RHSA-2026:60362
  • Red Hat Enterprise Linux BaseOS E4S (v.9.4) python-urllib3 1.26.5-5.el9_4.4, python3-urllib3 1.26.5-5.el9_4.4
    fixed: vendor fix RHSA-2026:60371
  • Red Hat Enterprise Linux BaseOS EUS (v.9.6) python-urllib3 1.26.5-6.el9_6.2, python3-urllib3 1.26.5-6.el9_6.2
    fixed: vendor fix RHSA-2026:59409
  • Red Hat Enterprise Linux High Availability AUS (v.8.4) resource-agents 4.1.1-90.el8_4.26, fence-agents-aws 4.2.1-65.el8_4.31, fence-agents-gce 4.2.1-65.el8_4.31, fence-agents-aliyun 4.2.1-65.el8_4.31, resource-agents-gcp 4.1.1-90.el8_4.26, fence-agents-azure-arm 4.2.1-65.el8_4.31, +1 more
    fixed: vendor fix RHSA-2026:51152

21 more fixed, 29 more not affected in the full advisory

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
5mo ago

Exploit prediction

0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 4.0 8.2 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
GitHub 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CNA 4.0 8.2 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/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
NVD 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
OSV 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem package affected fixed in
pypi urllib3
>=1.23, <2.7.0
2.7.0

Affected products

  • urllib3 urllib3

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.