Networking

Security Self-Checklist for Users of Unix

Passwords-your password is your first line of defense!
- Change your password often! It should be a combination of letters and digits, at least 7 characters, and should not contain dictionary words in any language.
- Don't ever write both your login and password down on the same piece of paper or keep them in the same place. (Beware of dumpster divers!)
- Be sure to logout properly and beware of someone looking over your shoulder when you log in.
- Don't let your "buddy" use your mason account. (Would you give this same buddy access to your bank account?)
Check your account for signs of tampering:
- Type:
```
ls -a
```
  and look for a file called .rhosts. .rhosts can enable someone to log in to your account with out a password. If you find it, delete it with:
```
rm .rhosts
```
Make a backup copy or printout of your .login file. Check it once or twice a semester to be sure it has not been tampered with. Be sure the umask is set as indicated below. This ensures that new files and directories are protected.
```
umask 077
```
Check file and directory permissions, especially your home directory and public_html directory:
```
ls -ld .
ls -ld public_html
```
Check to be sure that your directories are not "writeable." Only you should be able to write to your directories. For a tutorial on file/directories permissions and the chmod command see: chmod or
```
man chmod
```
Some FTP programs copy files and directories with writeable permissions. So if you ftp a file to mason, be sure to check the permissions afterward.
Delete SPAM and obvious hoaxes. Don't open attachments you aren't expecting. Keep antiviral software up to date: Network Associates
Make backups of precious files. Never keep only a single electronic copy of any file that is important. FTP a backup to disk or make a printout.

Click here to return to the IT 108 page