WordPress before 2.6.2 does not properly handle MySQL warnings about insertion of username strings that exceed the maximum column width of the user_login column, and does not properly handle space characters when comparing usernames, which allows remote attackers to change an arbitrary user's password to a random value by registering a similar username and then requesting a password reset, related to a "SQL column truncation vulnerability." NOTE: the attacker can discover the random password by also exploiting CVE-2008-4107.
http://marc.info/?l=oss-security&m=122152830017099&w=2
http://secunia.com/advisories/31737
http://secunia.com/advisories/31870
http://securityreason.com/securityalert/4272
http://securitytracker.com/id?1020869
https://www.exploit-db.com/exploits/6397
https://www.exploit-db.com/exploits/6421
https://www.redhat.com/archives/fedora-package-announce/2008-September/msg00607.html
https://www.redhat.com/archives/fedora-package-announce/2008-September/msg00629.html
http://wordpress.org/development/2008/09/wordpress-262/
http://www.debian.org/security/2009/dsa-1871