6.2.13 Ensure users' .netrc Files are not group or world accessible (Scored)
Profile Applicability
Level 1 - Server Level 1 - Workstation
Description
While the system administrator can establish secure permissions for users' .netrc files, the users can easily override these.
Rationale
.netrc files may contain unencrypted passwords that may be used to attack other systems.
Audit
Run the following script and verify no results are returned:
#!/bin/bash
for dir in `cat /etc/passwd | egrep -v '(root|sync|halt|shutdown)' | awk -F: '($7 != "/usr/sbin/nologin") { print $6 }'`; do
for file in $dir/.netrc; do
if [ ! -h "$file" -a -f "$file" ]; then
fileperm=`ls -ld $file | cut -f1 -d" "`
if [ `echo $fileperm | cut -c5 ` != "-" ]; then
echo "Group Read set on $file"
fi
if [ `echo $fileperm | cut -c6 ` != "-" ]; then
echo "Group Write set on $file"
fi
if [ `echo $fileperm | cut -c7 ` != "-" ]; then
echo "Group Execute set on $file"
fi
if [ `echo $fileperm | cut -c8 ` != "-" ]; then
echo "Other Read set on $file"
fi
if [ `echo $fileperm | cut -c9 ` != "-" ]; then
echo "Other Write set on $file"
fi
if [ `echo $fileperm | cut -c10 ` != "-" ]; then
echo "Other Execute set on $file"
fi
fi
done
done
Remediation
Making global modifications to users' files without alerting the user community can result in unexpected outages and unhappy users. Therefore, it is recommended that a monitoring policy be established to report user .netrc file permissions and determine the action to be taken in accordance with site policy.
Notes
While the complete removal of .netrc files is recommended if any are required on the system secure permissions must be applied.