smf-zombie is a SendmailTM filter for SPAM and virus filtration from zombie PC.
More than 80% of SPAM is going from the infected Windows computers (zombie PC).
This filter aims to be lightweight, reliable, and simple rather than have a myriad of options. It's written in C and works under Linux/BSD/Solaris.
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Here are some key features of "smf-zombie":
· It only scans the messages less than defined size;
· It has a hosts/networks whitelist;
· It blocks most of the SPAM/virus engines (up to the 95% of them);
· It checks sender IP with most reliable RBL - cbl.abuseat.org;
· It safely rejects "alien" bounces without RFC violating;
· It rejects messages for undisclosed recipients;
· It rejects harmful attachments to prevent virus spreading;
· It logs all filter activities to syslog.
· Small code (does not exceed 400 lines);
· Fast work;
· Stability (production quality);
· Low resources are required;
· No temporary files are created.