FreeBSD k5su Wheel Group Membership Validation Vulnerability

Bugtraq ID:	4777
Class:	Access Validation Error
CVE:
Remote:	No
Local:	Yes
Published:	May 20 2002 12:00AM
Updated:	May 20 2002 12:00AM
Credit:	This issue was reported in a FreeBSD Security Advisory.
Vulnerable:	FreeBSD FreeBSD 4.5 FreeBSD FreeBSD 4.4
Not Vulnerable:

FreeBSD k5su Wheel Group Membership Validation Vulnerability

k5su is a utility for the FreeBSD operating system which is similar to su.

To be used, the su utility normally requires that the local user is a member of the 'wheel' group. k5su does not sufficiently validate that the user possesses this group membership and may be used by arbitrary users who know the superuser password.

It should be noted that administrators must explicitly install k5su and this vulnerability is not present in default installations of the FreeBSD operating system.

FreeBSD k5su Wheel Group Membership Validation Vulnerability

Users must be authenticated locally and also possess authentication credentials for the superuser to take advantage of this issue.

FreeBSD k5su Wheel Group Membership Validation Vulnerability

Solution:
k5su is installed with the krb5 distribution and the utility is now disabled by default in the current version of FreeBSD-STABLE.

FreeBSD k5su Wheel Group Membership Validation Vulnerability

References: