The remote host is vulnerable to a Denial of Service (DoS) attack
The remote host is running Microsoft MSN Messenger. Certain versions of MSN messenger are vulnerable to a Denial of Service attack. Specifically, a message received with a large amount of data (HTML encoded spaces %20 in particular) in the font field of the message header can cause the MSN client to crash. This vulnerability can be exploited by a remote attacker to continuously crash a victim's IM client, causing a Denial of Service.
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