Microsoft is denying access to MSN Messenger clients older than version 6.2.0205. This is a response to Core Security’s advisory, which Microsoft followed with MS05-009. A malformed buddy image could exploit a vulnerable user’s instant messaging (IM) client. Microsoft even posted a dedicated page explaining the problem to IM users. This would be like refusing to let a person browse the Web because their version of Internet Explorer is too old, or to let them check mail because Outlook is out-of-date.”]
Source: https://taosecurity.blogspot.com/2005/02/kudos-to-microsoft-according-to-this.html