Sometimes Snort rules can contain useful information but are not practical to use in production. The Bleeding Snort rules recently added a set of rules to detect connection attempts to known compromised hosts. If you take a look at the rules, you'll see that it is essentially a large list of IP addresses.

When I first ran these rules on a Snort sensor, they definitely gave me some alerts requiring action. However, the performance of the sensor really suffered, particularly as the set of IP addresses grew. Since the rules were causing packet loss, I wanted to disable them.

At Eating Security.

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