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The Treacherous Power of Extended Regular Expressions

I wanted to filter out lines containing the word "line" or a double quote from a 1GB file. This can be easily specified as an extended regular expression, but it turns out that I got more than I bargained for.

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Location-Based Dictionary Attacks

I get daily security reports from the hosts I manage. Typically these contain invalid user attempts for users like guest, www, and root. (Although FreeBSD doesn't allow remote logins for root, I was surprised to find out that many Linux distributions allow them.)

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Creative Commons License Last update: Monday, February 17, 2020 5:56 pm
Unless otherwise expressly stated, all original material on this page created by Diomidis Spinellis is licensed under a Creative Commons Attribution-Share Alike 3.0 Greece License.