Very weird Call logs

I have call logs that look like this… Anyone have a clue?
Call Monitor

Datesort Time Caller ID Source Destination Duration Monitor
2014-03-26 00:08:23 “erotic” erotic s 12 sec
2014-03-26 00:08:23 “tiffany” tiffany s 12 sec
2014-03-26 00:08:23 “steelers” steelers s 13 sec
2014-03-26 00:08:23 “redskins” redskins s 13 sec
2014-03-26 00:08:22 “united” united s 11 sec
2014-03-26 00:08:22 “captain” captain s 12 sec
2014-03-26 00:08:22 “fucking” fucking s 12 sec
2014-03-26 00:08:22 “bigdick” bigdick s 12 sec
2014-03-26 00:08:21 “dennis” dennis s 11 sec
2014-03-26 00:08:21 “access” access s 11 sec
2014-03-26 00:08:21 “robert” robert s 11 sec
2014-03-26 00:08:21 “tigger” tigger s 11 sec
2014-03-26 00:08:20 “thomas” thomas s 12 sec
2014-03-26 00:08:20 “pbxvoip” pbxvoip s 12 sec
2014-03-26 00:08:20 “pbx2008” pbx2008 s 13 sec

Brute force…

Someone is trying to find their way in.