Login Request a demo
Medium severity · published Dec 26, 2018
CVE-2018-20217
A Reachable Assertion issue was discovered in the KDC in MIT Kerberos 5 (aka krb5) before 1.17
5.3
CVSS
1.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.4% · higher than 73% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
8.0; 9.0 · source: NVD
KE
Kerberos · Mit
before 5-1.17 · source: NVD
Affected product
DL
Debian Linux
Debian
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-20217
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-20217
Patch
http://krbdev.mit.edu/rt/Ticket/Display.html?id=8763
Patch
https://github.com/krb5/krb5/commit/5e6d1796106df8ba6bc1973ee0917c170d929086
Mailing List
https://lists.debian.org/debian-lts-announce/2019/01/msg00020.html
Mailing List
https://lists.debian.org/debian-lts-announce/2021/09/msg00019.html
lists.fedoraproject.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2KNHELH4YHNT6H2ESJWX2UIDXLBNGB2O/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20190416-0006/
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