Over the weekend, the amount IP addresses that brute force password guessing attacks originate from as detected by fail2ban, log scanning and automatic action script, has more than doubled from about 300 IPs per day to about 750 and that seems to be growing.

This pattern is usually indicative of some new Windows malware out in the wild successfully propagating to a huge number of machines that can then be used for things like password guessing and distributed denial of service attacks.

Relating to DDOS attacks, a large Botnet is attempting to use our DNS servers as DDOS amplifiers.  This won’t work because we have rate limiting configured on the external views for all of our servers, but it generated so much crap in the syslog’s that it ran some servers out of disk space.

As a result of this I’ve added code that bans IPs for an extended period if they exceed rate limit thresholds which both quieted down the logs and reduced CPU load on the name servers servers substantially.

The relevance to you is, if you are running Windows, make sure your anti-viral and anti-malware software and it’s databases are up to date and run scans frequently.

I recommend running Malware Bytes, as 9 times out of 10, when I have a customers computer that is infected, it’s the application that finds the infection.

Second thing, if your password is easily guessable, for example, a dictionary word, or a dictionary word with a number after it, it should be changed to something more complex.

An ideal password will contain no dictionary words, no proper names or anything related to your account such as your login, a combination of UPPER CASE, lower case, punctuation characters such as ~!@#$%^&*()_+=-`{}[]|:;”‘<>,.?/ and numbers 0123456789.