We took a look at 9 million delivery attempts through one of our spam filters and compiled a list of the most common spam connection rejection messages.
Spammers appear to have changed their software so that it less often sends the QUIT command, as required by the RFC.
Techniques for solving the CPU load issues caused by encrypted spam are discussed.
There have been reports from the Asterisk open-source PBX community that spammers are attempting to gain access to Asterisk PBX through brute-force attacks.
All about TLS-encrypted spam: Part II
All about TLS-encrypted spam: Part 1
First IPv6 Spam Message Caught in the Wild
Amazing new exploit for Linksys routers running DD-WRT
Transparent outbound filtering: An upcoming series of blog posts
Stats Porn Friday: How Traffic Shaping cuts out 2/3 more spam than blocking alone
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