CVE-2021-28363

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.13%
Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory gentoo.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/urllib3/urllib3/commits/main third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4S65ZQVZ2ODGB52IC7VJDBUK4M5INCXL/ vendor advisory
https://security.gentoo.org/glsa/202107-36 third party advisory vendor advisory
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory patch
https://pypi.org/project/urllib3/1.26.4/ third party advisory
https://github.com/urllib3/urllib3/commit/8d65ea1ecf6e2cdc27d42124e587c1b83a3118b0 third party advisory patch
https://github.com/urllib3/urllib3/security/advisories/GHSA-5phf-pp7p-vc2r third party advisory mitigation
https://security.gentoo.org/glsa/202305-02 vendor advisory
https://security.netapp.com/advisory/ntap-20240621-0007/

Frequently Asked Questions

What is the severity of CVE-2021-28363?
CVE-2021-28363 has been scored as a medium severity vulnerability.
How to fix CVE-2021-28363?
To fix CVE-2021-28363, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-28363 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28363 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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