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CVE-2021-28363

Published: Mar 15, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDU csafCWE-295
6.5MEDIUM
NVD MITRE
EPSS Score
2.1%
Top 20.0%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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

AV:NAC:LPR:NUI:NS:UC:LI:LA:N
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

python
oss-project·US
urllib3
OSS Libraries
fedoraproject
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?We can run the check for you — a free external exposure review, no install. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

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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