CVE-2017-11103

Published: 13 July 2017

Heimdal before 7.4 allows remote attackers to impersonate services with Orpheus' Lyre attacks because it obtains service-principal names in a way that violates the Kerberos 5 protocol specification. In _krb5_extract_ticket() the KDC-REP service name must be obtained from the encrypted version stored in 'enc_part' instead of the unencrypted version stored in 'ticket'. Use of the unencrypted version provides an opportunity for successful server impersonation and other attacks. NOTE: this CVE is only for Heimdal and other products that embed Heimdal code; it does not apply to other instances in which this part of the Kerberos 5 protocol specification is violated.

Priority

Cvss 3 Severity Score

8.1

Score breakdown

Status

Package	Release	Status
heimdal Launchpad, Ubuntu, Debian	trusty	Released (1.6~git20131207+dfsg-1ubuntu1.2)
	upstream	Needs triage
	xenial	Released (1.7~git20150920+dfsg-4ubuntu1.16.04.1)
	yakkety	Released (1.7~git20150920+dfsg-4ubuntu1.16.10.1)
	zesty	Released (7.1.0+dfsg-9ubuntu1.1)
samba Launchpad, Ubuntu, Debian	trusty	Released (2:4.3.11+dfsg-0ubuntu0.14.04.10)
	upstream	Needs triage
	xenial	Released (2:4.3.11+dfsg-0ubuntu0.16.04.9)
	yakkety	Released (2:4.4.5+dfsg-2ubuntu5.8)
	zesty	Released (2:4.5.8+dfsg-0ubuntu0.17.04.4)

Severity score breakdown

Parameter	Value
Base score	8.1
Attack vector	Network
Attack complexity	High
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

References

Bugs

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