DOKK / manpages / debian 10 / chkrootkit / chkwtmp.1.en
CHKWTMP(1) General Commands Manual CHKWTMP(1)

chkwtmp - check wtmp-file for deleted entries

chkwtmp

Chkwtmp examines the file /var/log/wtmp for entries with no information (containing only null-bytes). If such entries are found the program prints the time window for the original entry. This is done by displaying the timestamps of the wtmp-entry before and after the deleted entry.

To run chkwtmp you need read permission on the file /var/log/wtmp. Normally this file is world-readable and no special privileges are required to run the checker.

/var/log/wtmp
login data base

wtmp(4), who(1)

An entry is recognized as overwritten if the time-information has been overwritten with null-bytes.

This program was designed to run on SunOS 4.x systems only. On other systems the output is undefined...

Thu Oct 12 1994 7th Edition