system-tools-backends before 2.6.0-1ubuntu1.1 in Ubuntu 8.10, as used by "Users and Groups" in GNOME System Tools, hashes account passwords with 3DES and consequently limits effective password lengths to eight characters, which makes it easier for context-dependent attackers to successfully conduct brute-force password attacks.
https://launchpad.net/bugs/287134
https://exchange.xforce.ibmcloud.com/vulnerabilities/50435
http://www.ubuntu.com/usn/usn-663-1