BusyBox 1.1.1 does not use a salt when generating passwords, which makes it easier for local users to guess passwords from a stolen password file using techniques such as rainbow tables.
https://exchange.xforce.ibmcloud.com/vulnerabilities/25569
http://support.avaya.com/elmodocs2/security/ASA-2007-250.htm
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9483
https://euvd.enisa.europa.eu/vulnerability/EUVD-2006-1062
http://www.securityfocus.com/bid/17330
http://www.redhat.com/support/errata/RHSA-2007-0244.html
http://secunia.com/advisories/25848
http://secunia.com/advisories/25098