CVE-2018-20217

Description

A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17. If an attacker can obtain a krbtgt ticket using an older encryption type (single-DES, triple-DES, or RC4), the attacker can crash the KDC by making an S4U2Self request.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.88% Top 30%
Vendor Advisory fedoraproject.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2KNHELH4YHNT6H2ESJWX2UIDXLBNGB2O/ vendor advisory
http://krbdev.mit.edu/rt/Ticket/Display.html?id=8763 third party advisory patch
https://github.com/krb5/krb5/commit/5e6d1796106df8ba6bc1973ee0917c170d929086 third party advisory patch
https://lists.debian.org/debian-lts-announce/2019/01/msg00020.html third party advisory mailing list
https://security.netapp.com/advisory/ntap-20190416-0006/ third party advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00019.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2018-20217?
CVE-2018-20217 has been scored as a medium severity vulnerability.
How to fix CVE-2018-20217?
To fix CVE-2018-20217, 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-2018-20217 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-20217 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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