CVE-2018-20217

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 v3.0 5.3 MEDIUM
CVSS v2.0 3.5 LOW

5.3^/10

CVSS v3.0 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

3.5^/10

CVSS v2.0 : LOW

Vector : AV:N/AC:M/Au:S/C:N/I:N/A:P

Exploitability : 6.8 / Impact : 2.9

Access Vector NETWORK

Access Complexity MEDIUM

Authentication SINGLE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact PARTIAL

References

Link	Resource
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2KNHELH4YHNT6H2ESJWX2UIDXLBNGB2O/	Third Party Advisory
https://github.com/krb5/krb5/commit/5e6d1796106df8ba6bc1973ee0917c170d929086	Patch Third Party Advisory
http://krbdev.mit.edu/rt/Ticket/Display.html?id=8763	Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2019/01/msg00020.html	Mailing List Third Party Advisory
https://security.netapp.com/advisory/ntap-20190416-0006/	Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/09/msg00019.html	Mailing List Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:mit:kerberos:*:*:*:*:*:*:*:*

Configuration 2 (hide)

OR	cpe:2.3:o:debian:debian_linux:8.0:::::::*
	cpe:2.3:o:debian:debian_linux:9.0:::::::*

Information

Published : 2018-12-26 13:29

Updated : 2021-10-18 05:03

NVD link : CVE-2018-20217

Mitre link : CVE-2018-20217

JSON object : View

CWE

CWE-617

Reachable Assertion

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Products Affected

debian

debian_linux

mit

kerberos

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