#
# Copyright 2015, Patrick Muench
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# author: Christoph Hartmann
# author: Dominik Richter
# author: Patrick Muench
login_defs_umask = attribute('login_defs_umask', value: os.redhat? ? '077' : '027', description: 'Default umask to set in login.defs')
login_defs_passmaxdays = attribute('login_defs_passmaxdays', value: '60', description: 'Default password maxdays to set in login.defs')
login_defs_passmindays = attribute('login_defs_passmindays', value: '7', description: 'Default password mindays to set in login.defs')
login_defs_passwarnage = attribute('login_defs_passwarnage', value: '7', description: 'Default password warnage (days) to set in login.defs')
shadow_group = 'root'
shadow_group = 'shadow' if os.debian? || os.suse? || os.name == 'alpine'
container_execution = begin
virtualization.role == 'guest' && virtualization.system =~ /^(lxc|docker)$/
rescue NoMethodError
false
end
blacklist = attribute(
'blacklist',
value: suid_blacklist.default,
description: 'blacklist of suid/sgid program on system'
)
control 'os-01' do
impact 1.0
title 'Trusted hosts login'
desc "hosts.equiv file is a weak implemenation of authentication. Disabling the hosts.equiv support helps to prevent users from subverting the system's normal access control mechanisms of the system."
describe file('/etc/hosts.equiv') do
it { should_not exist }
end
end
control 'os-02' do
impact 1.0
title 'Check owner and permissions for /etc/shadow'
desc 'Check periodically the owner and permissions for /etc/shadow'
describe file('/etc/shadow') do
it { should exist }
it { should be_file }
it { should be_owned_by 'root' }
its('group') { should eq shadow_group }
it { should_not be_executable }
it { should_not be_readable.by('other') }
end
if os.redhat? || os.name == 'fedora'
describe file('/etc/shadow') do
it { should_not be_writable.by('owner') }
it { should_not be_readable.by('owner') }
end
else
describe file('/etc/shadow') do
it { should be_writable.by('owner') }
it { should be_readable.by('owner') }
end
end
if os.debian? || os.suse?
describe file('/etc/shadow') do
it { should be_readable.by('group') }
end
else
describe file('/etc/shadow') do
it { should_not be_readable.by('group') }
end
end
end
control 'os-03' do
impact 1.0
title 'Check owner and permissions for /etc/passwd'
desc 'Check periodically the owner and permissions for /etc/passwd'
describe file('/etc/passwd') do
it { should exist }
it { should be_file }
it { should be_owned_by 'root' }
its('group') { should eq 'root' }
it { should_not be_executable }
it { should be_writable.by('owner') }
it { should_not be_writable.by('group') }
it { should_not be_writable.by('other') }
it { should be_readable.by('owner') }
it { should be_readable.by('group') }
it { should be_readable.by('other') }
end
end
control 'os-04' do
impact 1.0
title 'Dot in PATH variable'
desc 'Do not include the current working directory in PATH variable. This makes it easier for an attacker to gain extensive rigths by executing a Trojan program'
describe os_env('PATH') do
its('split') { should_not include('') }
its('split') { should_not include('.') }
end
end
control 'os-05' do
impact 1.0
title 'Check login.defs'
desc 'Check owner and permissions for login.defs. Also check the configured PATH variable and umask in login.defs'
describe file('/etc/login.defs') do
it { should exist }
it { should be_file }
it { should be_owned_by 'root' }
its('group') { should eq 'root' }
it { should_not be_executable }
it { should be_readable.by('owner') }
it { should be_readable.by('group') }
it { should be_readable.by('other') }
end
describe login_defs do
its('ENV_SUPATH') { should include('/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin') }
its('ENV_PATH') { should include('/usr/local/bin:/usr/bin:/bin') }
its('UMASK') { should include(login_defs_umask) }
its('PASS_MAX_DAYS') { should eq login_defs_passmaxdays }
its('PASS_MIN_DAYS') { should eq login_defs_passmindays }
its('PASS_WARN_AGE') { should eq login_defs_passwarnage }
its('LOGIN_RETRIES') { should eq '5' }
its('LOGIN_TIMEOUT') { should eq '60' }
its('UID_MIN') { should eq '1000' }
its('GID_MIN') { should eq '1000' }
end
end
control 'os-05b' do
impact 1.0
title 'Check login.defs - RedHat specific'
desc 'Check owner and permissions for login.defs. Also check the configured PATH variable and umask in login.defs'
describe file('/etc/login.defs') do
it { should_not be_writable }
end
describe login_defs do
its('SYS_UID_MIN') { should eq '201' }
its('SYS_UID_MAX') { should eq '999' }
its('SYS_GID_MIN') { should eq '201' }
its('SYS_GID_MAX') { should eq '999' }
end
only_if { os.redhat? }
end
control 'os-06' do
impact 1.0
title 'Check for SUID/ SGID blacklist'
desc 'Find blacklisted SUID and SGID files to ensure that no rogue SUID and SGID files have been introduced into the system'
describe suid_check(blacklist) do
its('diff') { should be_empty }
end
end
control 'os-07' do
impact 1.0
title 'Unique uid and gid'
desc 'Check for unique uids gids'
describe passwd do
its('uids') { should_not contain_duplicates }
end
describe etc_group do
its('gids') { should_not contain_duplicates }
end
end
control 'os-08' do
impact 1.0
title 'Entropy'
desc 'Check system has enough entropy - greater than 1000'
describe file('/proc/sys/kernel/random/entropy_avail').content.to_i do
it { should >= 1000 }
end
end
control 'os-09' do
impact 1.0
title 'Check for .rhosts and .netrc file'
desc 'Find .rhosts and .netrc files - CIS Benchmark 9.2.9-10'
output = command('find / -maxdepth 3 \( -iname .rhosts -o -iname .netrc \) -print 2>/dev/null | grep -v \'^find:\'')
out = output.stdout.split(/\r?\n/)
describe out do
it { should be_empty }
end
end
control 'os-10' do
impact 1.0
title 'CIS: Disable unused filesystems'
desc '1.1.1 Ensure mounting of cramfs, freevxfs, jffs2, hfs, hfsplus, squashfs, udf, FAT'
only_if { !container_execution }
efi_dir = inspec.file('/sys/firmware/efi')
describe file('/etc/modprobe.d/dev-sec.conf') do
its(:content) { should match 'install cramfs /bin/true' }
its(:content) { should match 'install freevxfs /bin/true' }
its(:content) { should match 'install jffs2 /bin/true' }
its(:content) { should match 'install hfs /bin/true' }
its(:content) { should match 'install hfsplus /bin/true' }
its(:content) { should match 'install squashfs /bin/true' }
its(:content) { should match 'install udf /bin/true' }
# if efi is active, do not disable vfat. otherwise the system
# won't boot anymore
unless efi_dir.exist?
its(:content) { should match 'install vfat /bin/true' }
end
end
end
control 'os-11' do
impact 1.0
title 'Protect log-directory'
desc 'The log-directory /var/log should belong to root'
describe file('/var/log') do
it { should be_directory }
it { should be_owned_by 'root' }
its(:group) { should match(/^root|syslog$/) }
end
end
