Title

Anonymous FTP accounts must not have a functional shell. (Cat I impact)

Discussion

If an anonymous FTP account has been configured to use a functional shell, attackers could gain access to the shell if the account is compromised.

Check Content

Check the shell for the anonymous FTP account. # cat /etc/passwd | grep "^ftp" | cut -f 7,7 -d ":" | \ egrep -c -i "\/bin\/false|\/dev\/null|\/usr\/bin\/false|\/bin\/true|\/sbin\/nologin" This is a finding if the seventh field is empty (the entry ends with a colon[:]) or if the seventh field does not contain one of the following: /bin/false /dev/null /usr/bin/false /bin/true /sbin/nologin

Fix Text

Configure anonymous FTP accounts to use a non-functional shell. If necessary, edit the /etc/passwd file to remove any functioning shells associated with the FTP account and replace them with non-functioning shells, such as /dev/null.

Additional Identifiers

Rule ID: SV-35106r1_rule

Vulnerability ID: V-4387

Group Title: GEN005000

Expert Comments

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