Title

The SSH daemon must use privilege separation. (Cat II impact)

Discussion

SSH daemon privilege separation causes the SSH process to drop root privileges when not needed, which would decrease the impact of software vulnerabilities in the unprivileged section.

Check Content

Check the SSH daemon configuration. Note that keywords are case-insensitive and arguments (args) are case-sensitive. keyword=UsePrivilegeSeparation 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 "UsePrivilegeSeparation" If the return value is no, this is a finding.

Fix Text

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

Additional Identifiers

Rule ID: SV-35139r1_rule

Vulnerability ID: V-22486

Group Title: GEN005537

Expert Comments

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