Strange file names

[Oki DZ <litbang@haltek.telkom.net.id>]

Hi,

I have some strange files. Do they have to exist in /usr/bin?
ss1:/usr/bin$ ls -l | more
total 9010
-rwxr-xr-x   2 root     root        20720 Dec 24  1998 [
-rwxr-xr-x   1 root     root       107956 Feb 24  1999 a2p
lrwxrwxrwx   1 root     root            4 Nov 16 03:44 aaaa -> host
-rwxr-xr-x   1 root     root        14416 Feb 24  1999 ab

Or, does it mean that this system has been cracked?
Or am I just being paranoid?

Oki

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