212-77 Sample Questions Answers

No changes in how the command runs would occur.

Users could no longer change their passwords because they do not have write permissions to /etc/passwd.

Users' passwords would not expire.

Shadow passwords would quit working.

Disable a service in the appropriate /etc/xinetd.d configuration file.

Use a firewall to drop all requests to unneeded services.

Block service requests with the appropriate commands in /etc/hosts.deny.

Uninstall unneeded network services.

hosts.deny takes precedence; the client is denied access to the server.

hosts.allow takes precedence; the client is granted access to the server.

The system's administrator is paged to decide whether to allow access.

TCP Wrappers refuses to run and logs an error in /var/log/messages.

fdisk

mkfs

newfs

fsck

The intruder could reboot it, reconfigure it to boot from floppy, boot a DOS floppy, and use DOS's disk utilities to delete the Linux partitions and erase the hard disk.

The intruder could open the case, remove the hard disk and insert it in another computer, then modify the configuration files and return the hard disk to the original machine.

The intruder could run a password-cracking program on the system's /etc/passwd file, thus obtaining all the user's passwords for use in further compromising the system at a later date.

The intruder could utilize a bug in su, passwd, or some other SUID root program to acquire root privileges and then alter the system's configuration files.

Use du .

Use df .

Use du /

Use df

Use df /

CRFS

FS

FDISK

MKFS

Before doing anything else, install the application on a production computer and see if you still have the same problems.

The log files associated with the application.

The Web site home page for the application.

Newsgroups where other users discuss the application.

Keep a copy of each user's password in a locked filing cabinet in the same room as the Linux server.

Record the inode number of every file in a binder in the same room as the Linux server.

Record the hardware configuration details in a binder in the same room as the Linux server.

Keep a copy of key configuration files on a different partition on the same computer.

Change all the passwords in the /etc/passwd file to x.

Implement shadow passwords using the spasswd command.

Change all the passwords in the /etc/passwd file to *.

Implement shadow passwords using the pwconv command.

Bugs in the programs may cause more damage than they would in ordinary programs.

The program files are large and thus may cause a disk to run out of space.

Because the programs require password entry, running them over an insecure network link runs the risk of password interception.

Users may be able to abuse a program's features, thus doing more damage than would otherwise be possible.

/etc/shadow

/etc/.passwd

/etc/passwd

/.secure/.htaccess