Title

Files executed through a mail aliases file must be owned by root and must reside within a directory owned and writable only by root. (Cat I impact)

Discussion

If a file executed through a mail aliases file is not owned and writable only by root, it may be subject to unauthorized modification. Unauthorized modification of files executed through aliases may allow unauthorized users to attain root privileges.

Check Content

Examine the aliases file for any utilized directories or paths. # cat/etc/mail/aliases | cut -f 2,2 -d ":" | grep "|" For example, the alias file entry will look like: msgs: "|/usr/bin/msgs -s" The entry must be an absolute path name: # ls -lLd `dirname <entry>` # ls -lL <entry> If the file or parent directory is not owned by root, this a finding.

Fix Text

Edit the /etc/mail/aliases file Locate the entries executing a program. They will appear similar to the following line: alias: "|/usr/local/bin/ls" (or some other program name) Ensure root owns the programs and the directory(ies) they reside in by using the chown command to change owner to root. For a directory entry: # chown root <entry> For a file entry (change BOTH the directory and file, where/as necessary: # chown root <entry> # chown root `dirname <entry>`

Additional Identifiers

Rule ID: SV-35169r1_rule

Vulnerability ID: V-833

Group Title: GEN004400

Expert Comments

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