Mass Port 445 attack imminent says Symantec

For all to read this is a bit disturbing, the following quote is from the Symantec Web Site.
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An ominous increase in sniffing activity on TCP Port 445 could signal an impending mass malicious code attack targeting a recently patched Microsoft vulnerability, according to a warning from security researchers.

Researchers at Symantec Corp.'s DeepSight Network have detected a surge in scans on Port 445, an indication that malicious hackers may have already created exploits for a flaw in Microsoft Corp.'s implementation of the SMB (Server Message Block) protocol.
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The vulnerability, which was rated "critical," was patched one week ago in Microsoft's MS05-027 bulletin, and the increased noise on that port could be the first sign that a password brute force attack is imminent, Symantec DeepSight warned.