Evaluation of XCCDF content¶

$ oscap-ssh user@host 22 xccdf eval [options] INPUT_CONTENT

Only source datastreams are supported as INPUT_CONTENT!

Supported options are:
--profile
--tailoring-file
--tailoring-id
--cpe
--results
--results-arf
--report
--skip-valid
--fetch-remote-resources
--progress
--datastream-id
--xccdf-id
--benchmark-id
--remediate

Evaluation of OVAL content¶

$ oscap-ssh user@host 22 oval eval [options] INPUT_CONTENT

Supported options are:
--id
--variables
--directives
--results
--report
--skip-valid
--datastream-id
--oval-id
--probe-root (has to be remote path)

Collection of OVAL System Characteristic¶

$ oscap-ssh user@host 22 oval collect [options] INPUT_CONTENT

Supported options are:
--id
--syschar
--variables
--skip-valid

Specific option for oscap-ssh (must be first argument):
--sudo

Environment variables¶

oscap-ssh checks out the SSH_ADDITIONAL_OPTIONS environment variable, and pastes its contents into the command-line of ssh to the location where options are expected. Supply the variable in form of a string that corresponds to a section of the ssh command-line and that consists of options you want to pass.

Simple XCCDF evaluation¶

The following command evaluates a remote Fedora machine as root. HTML report is written out as report.html on the local machine. Can be executed from any machine that has ssh, scp and bash. The local machine does not need to have openscap installed. It also uses the SSH_ADDITIONAL_OPTIONS variable to configure ssh in such way that contents of the known_hosts file are ignored.

$ export SSH_ADDITIONAL_OPTIONS="-o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null" $ oscap-ssh root@192.168.1.13 22 xccdf eval --profile xccdf_org.ssgproject.content_profile_common --report report.html /usr/share/xml/scap/ssg/content/ssg-fedora-ds.xml

XCCDF Evaluation with tailoring file¶

The following command uses a tailoring file and also copies back ARF and XCCDF results. The tailoring file is automatically copied from local machine to remote.

$ oscap-ssh --sudo oscap-user@192.168.1.13 22 xccdf eval --profile xccdf_org.ssgproject.content_profile_common --report report.html --results results.xml --results-arf arf.xml --tailoring-file ssg-fedora-ds-tailoring.xml /usr/share/xml/scap/ssg/content/ssg-fedora-ds.xml

Running remotely as root¶

Note that the openscap scanner is best run by the 'root' user as in the first example above. To do this, the "PermitRootLogin" directive must be enabled in /etc/ssh/sshd_config, which is itself a security violation. A safer approach is to enable a non-privileged user ('oscap-user' in the second example above) to run only the oscap binary as root (with the '--sudo' flag) by updating the remote machine's 'sudoers' file or adding a file like /etc/sudoers.d/99-oscap-user:
# allow oscap-user to run openscap scanner
Defaults!/usr/bin/oscap !requiretty
oscap-user ALL=(root) NOPASSWD: /usr/bin/oscap