Over the past few months Hotmail users have been made aware of hijacking of user accounts on the free Microsoft email service. Once access is obtained, still by unknown means, the hijackers send spam to the whole address book of the victim. There have also been reports of emails or contacts being deleted, and emails being sent to unknown address or other spam lists.
Microsoft seems to think that there is a phishing attack getting the user credentials or this is the work of a virus/worm. My guess is that it is a full on assault on Hotmail using both methods. Just today I received an email from a known contact with this in the body:
An interesting part to this email is that this is a standard closing that this person uses, perhaps in a signature file. At the end of the day this becomes a nightmare to email system administrators. This is a significant amount of spam coming from a previously trusted source. I have not tested out the link that I removed above but I am guessing that if I visit that site there will be a drive by download of a virus or trojan.
My preferred free web based email service is Gmail, it may be time for every loyal Hotmail user to consider switching.