Title

The SSH daemon must perform strict mode checking of home directory configuration files. (Cat II impact)

Discussion

If other users have access to modify user-specific SSH configuration files, they may be able to log into the system as another user.

Check Content

Check the SSH daemon configuration. Note that keywords are case-insensitive and arguments (args) are case-sensitive. keyword=StrictModes arg(s)=yes Default values include: "yes" Note: When the default "arg" value exactly matches the required "arg" value (see above), the <keyword=arg> entry is not required to exist (commented or uncommented) in the ssh (client) or sshd (server) configuration file. While not required, it is recommended that the configuration file(s) be populated with all keywords and assigned arg values as a means to explicitly document the ssh(d) binary's expected behavior. Examine the file. # cat /opt/ssh/etc/sshd_config | tr '\011' ' ' | tr -s ' ' | sed -e 's/^[ \t]*//' | grep -v '^#' | grep -i "StrictModes" If the return value is no, this is a finding.

Fix Text

Edit the SSH daemon configuration and add or edit the StrictModes setting value to yes.

Additional Identifiers

Rule ID: SV-35137r1_rule

Vulnerability ID: V-22485

Group Title: GEN005536

Expert Comments

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