CVE Vulnerabilities

CVE-2021-28363

Improper Certificate Validation

Published: Mar 15, 2021 | Modified: Jun 21, 2024
CVSS 3.x
6.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CVSS 2.x
6.4 MEDIUM
AV:N/AC:L/Au:N/C:P/I:P/A:N
RedHat/V2
RedHat/V3
6.5 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Ubuntu
MEDIUM

The urllib3 library 1.26.x before 1.26.4 for Python omits SSL certificate validation in some cases involving HTTPS to HTTPS proxies. The initial connection to the HTTPS proxy (if an SSLContext isnt given via proxy_config) doesnt verify the hostname of the certificate. This means certificates for different servers that still validate properly with the default urllib3 SSLContext will be silently accepted.

Weakness

The product does not validate, or incorrectly validates, a certificate.

Affected Software

Name Vendor Start Version End Version
Urllib3 Python 1.26.0 (including) 1.26.4 (excluding)
Red Hat OpenShift Container Platform 3.11 RedHat python-urllib3-1:1.24.3-2.el7 *
Python-pip Ubuntu devel *
Python-pip Ubuntu trusty *
Python-pip Ubuntu upstream *
Python-urllib3 Ubuntu devel *
Python-urllib3 Ubuntu trusty *
Python-urllib3 Ubuntu upstream *

Potential Mitigations

References