All FTP users must have a default umask of 077.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-12011	GEN005040	SV-45887r1_rule		Medium

Description
The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask is stored as a 4-digit number, the first digit representing special access modes is typically ignored or required to be zero (0).

STIG	Date
SUSE Linux Enterprise Server v11 for System z Security Technical Implementation Guide	2018-09-19

Details

Check Text ( C-43204r1_chk )
Check the umask setting for FTP users. Procedure: For gssftp: Assuming an anonymous ftp user has been defined with no user initialization script invoked to change the umask # ftp localhost Name: (localhost:root): anonymous Password: anything ftp>umask If the umask value returned is not 077, this is a finding. or: # grep "server_args" /etc/xinetd.d/gssftp The default umask for FTP is "023" if the server _args entry does not contain "-u 077" this is a finding. For vsftp: # grep "_mask" /etc/vsftpd/vsftpd.conf The default "local_umask" setting is 077. If this has been changed, or the "anon_umask" setting is not 077, this is a finding.

Check Text ( C-43204r1_chk )

Check the umask setting for FTP users.

Procedure:

For gssftp:
Assuming an anonymous ftp user has been defined with no user initialization script invoked to change the umask
# ftp localhost
Name: (localhost:root): anonymous
Password: anything
ftp>umask

If the umask value returned is not 077, this is a finding.
or:
# grep "server_args" /etc/xinetd.d/gssftp

The default umask for FTP is "023" if the server _args entry does not contain "-u 077" this is a finding.

For vsftp:
# grep "_mask" /etc/vsftpd/vsftpd.conf
The default "local_umask" setting is 077. If this has been changed, or the "anon_umask" setting is not 077, this is a finding.

Fix Text (F-39265r1_fix)
Edit the initialization files for the ftp user and set the umask to 077. Procedure: For gssftp: Modify the /etc/xinetd.d/gssftp file adding "-u 077" to the server_args entry. For vsftp: Modify the "/etc/vsftpd/vsftpd.conf" setting "local_umask" and "anon_umask" to 077.