CVE-2021-28363

Published: Mar 15, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDU csafCWE-295

6.5MEDIUM

NVD MITRE

Description

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 isn't given via proxy_config) doesn't 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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:LConfidentiality

Low

I:LIntegrity

Low

A:NAvailability

None

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Weaknesses

CWE-295

Affected Products

oss-project·US

oss-project·USaka fedora project

fedoraOn-premOS

Operating Systems / linux-distro

oracle

commercial·USaka oracle corp.

peoplesoft enterprise peopletoolsOn-premWeb App

Enterprise Software / itsm-monitoring

Сообщество свободного программного обеспечения

oss-projectaka fsf

Debian GNU/LinuxOn-premOS

Operating Systems / linux-distro

ООО «РусБИТех-Астра»

commercial·RUaka rusbitech-astra

Astra Linux Special EditionOn-premOS

Operating Systems / linux-distro

Andrey Petrov

individual-devaka andrey-petrov

urllib3Library

OSS Libraries / pypi

and 2 more affected products View all →

Exploitability

Official Patch Available

Workaround Available

Is your org exposed to CVE-2021-28363?Request an assessment to establish which checks are appropriate for your systems. Check my exposure

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Collection

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References

https://github.com/urllib3/urllib3/commits/main

github.com

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/

lists.fedoraproject.org

https://security.gentoo.org/glsa/202107-36

security.gentoo.org

and 32 more references View all →

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