我变得偏执，运行 chkrootkit 和 rkhunter 来扫描 rootkit。看起来 chkrootkit 没有发现任何东西，但 rkhunter 返回了一些警告。我认为很多可能是误报，但我最担心的是“可能的 rootkit 字符串”和三个可疑文件。任何解释将不胜感激！谢谢！
Performing file properties checks
/usr/bin/fuser [ Warning ]
/usr/bin/whatis [ Warning ]
/usr/bin/shasum [ Warning ]
Performing additional rootkit checks
Checking for possible rootkit strings [ Warning ]
Performing checks on the network interfaces
Checking for promiscuous interfaces [ Warning ]
Performing system boot checks
Checking for system startup files [ Warning ]
Performing system configuration file checks
Checking if SSH root access is allowed [ Warning ]
Checking if SSH protocol v1 is allowed [ Warning ]
Performing filesystem checks
Checking for hidden files and directories [ Warning ]
日志文件中的警告：
[17:00:44] Info: No mail-on-warning address configured
[17:01:25] /usr/bin/fuser [ Warning ]
[17:01:25] Warning: The command '/usr/bin/fuser' has been replaced by a script: /usr/bin/fuser: a /usr/bin/perl -w script text executable, ASCII text
[17:01:36] /usr/bin/whatis [ Warning ]
[17:01:36] Warning: The command '/usr/bin/whatis' has been replaced by a script: /usr/bin/whatis: POSIX shell script text executable, ASCII text
[17:01:37] /usr/bin/shasum [ Warning ]
[17:01:37] Warning: The command '/usr/bin/shasum' has been replaced by a script: /usr/bin/shasum: a /usr/bin/perl script text executable, ASCII text
[17:03:28] Warning: Checking for possible rootkit strings [ Warning ]
[17:04:07] Checking for promiscuous interfaces [ Warning ]
[17:04:07] Warning: Possible promiscuous interfaces:
[17:04:09] Checking for system startup files [ Warning ]
[17:04:09] Warning: No system startup files found.
[17:04:10] Checking if SSH root access is allowed [ Warning ]
[17:04:10] Warning: The SSH configuration option 'PermitRootLogin' has not been set.
[17:04:10] Checking if SSH protocol v1 is allowed [ Warning ]
[17:04:10] Warning: The SSH configuration option 'Protocol' has not been set.
[17:04:17] Checking for hidden files and directories [ Warning ]
[17:04:17] Warning: Hidden file found: /usr/share/man/man5/.rhosts.5: troff or preprocessor input text, ASCII text