If the gigantic distributed denial of service (DDoS) attacks against the spam blacklisting operation Spamhaus wasn’t proof enough: spammers have trouble steering around blacklists and other reputation-based filters. Even if the language in their message is generic enough to avoid detection, dropping a link to a known, malicious- or compromised domain is plenty to get an entire message dropped.
Spammers without a legion of 100,000 bots at their fingertips have to get creative about getting their message into the target’s inbox. Lately, a method that’s drawing attention is to leverage low-security redirection services to whitewash a link to a ‘known-malicious’ or merely suspicious sites.
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