Red Hat Security Advisory RHSA-2001:014-03 - A locally exploitable buffer overflow was found in the crontab command in the handling of long usernames - If the system administrator has created usernames 20 characters long, it is possible for those users to gain elevated privileges.
c9d942e6d811a70f2061f713b8b18bc5e93bc8d091867ffd6a3f723608aeeddc