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CVE-2021-28363

Published: Mar 15, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSA BDU csafCWE-295
NVD MITRE
6.5CVSSMEDIUM
EPSS Score
2.1%
Top 20.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

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.

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
Open in CVSS calculator →

Weaknesses

CWE-295

Affected Products

urllib3pythonOSS Libraries
fedorafedoraproject
On-premOS
Operating Systems / linux-distro
peoplesoft enterprise peopletoolsoracle
On-premWeb App
Enterprise Software / itsm-monitoring
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
Astra Linux Special EditionООО «РусБИТех-Астра»
On-premOS
Operating Systems / linux-distro
pythonoss-projectUSOSS Libraries
fedoraprojectoss-projectUSOperating Systemsaka fedora project
oraclecommercialUSDatabasesaka oracle corp.
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
ооо «русбитех-астра»commercialRUOperating Systemsaka rusbitech-astra
and 3 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available
Workaround Available

MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0
github.com
https://github.com/urllib3/urllib3/commits/main
github.com
https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2r
github.com
and 32 more references View all →

Timeline

Published
Mar 15, 2021
Last Updated
Nov 21, 2024

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