A vulnerability has been identified with MD5 hashing that would allow an attacker to basically impersonate any SSL-secured website on the Internet. This is going to have serious and far-reaching implications. Combine that with the number of computers out there that are compromised by some virus or malware that has hijacked the hosts file, and it would be pretty easy to start collecting credit card numbers, bank account info, etc. You can read the full details here.
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