“The specific flaw exists within the ‘skype4com’ URI handler created by Skype during installation. When processing short string values through this handler an exploitable memory corruption may occur which can result in arbitrary code execution under the context of the current user.[…]
Skype has corrected this issue as of 11/15/2007. All clients updated or installed as of that date are patched to this issue.”
Successful exploitation of the flaw requires user interaction, as hackers first need to lure unsuspecting victims onto malicious pages.
The vulnerability affects all Skype version prior to 220.127.116.11.