CVE-2021-28861

Description

Python 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure. NOTE: this is disputed by a third party because the http.server.html documentation page states "Warning: http.server is not recommended for production. It only implements basic security checks."

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
EPSS 0.47%
Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory gentoo.org Vendor Advisory python.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://bugs.python.org/issue43223 vendor advisory issue tracking
https://github.com/python/cpython/pull/93879 third party advisory patch
https://github.com/python/cpython/pull/24848 third party advisory patch
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OKYE2DOI2X7WZXAWTQJZAXYIWM37HDCY/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LTSPFIULY2GZJN3QYNFVM4JSU6H4D6J/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S7G66SRWUM36ENQ3X6LAIG7HAB27D4XJ/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/DISZAFSIQ7IAPAEQTC7G2Z5QUA2V2PSW/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QLE5INSVJUZJGY5OJXV6JREXWD7UDHYN/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HPX4XHT2FGVQYLY2STT2MRVENILNZTTU/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X46T4EFTIBXZRYTGASBDEZGYJINH2OWV/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KRGKPYA5YHIXQAMRIXO5DSCX7D4UUW4Q/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I3MQT5ZE3QH5PVDJMERTBOCILHK35CBE/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2TRINJE3INWDVIHIABW4L2NP3RUSK7BJ/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WXF6MQ74HVIDDSR5AE2UDR24I6D4FEPC/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IFGV7P2PYFBMK32OKHCAC2ZPJQV5AUDF/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TZEPOPUFC42KXXSLFPZ47ZZRGPOR7SQE/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5OABQ5CMPQETJLFHROAXDIDXCMDTNVYG/ vendor advisory
https://security.gentoo.org/glsa/202305-02 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-28861?
CVE-2021-28861 has been scored as a high severity vulnerability.
How to fix CVE-2021-28861?
To fix CVE-2021-28861, 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-2021-28861 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28861 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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