diff --git a/tests/hardening/5.1.8_cron_users.sh b/tests/hardening/5.1.8_cron_users.sh
index b333419..80807b8 100644
--- a/tests/hardening/5.1.8_cron_users.sh
+++ b/tests/hardening/5.1.8_cron_users.sh
@@ -6,5 +6,54 @@ test_audit() {
     # shellcheck disable=2154
     run blank /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
 
-    # TODO fill comprehensive tests
+    local test_user="testcrontabduser"
+
+    describe Tests purposely failing
+    touch /etc/cron.deny /etc/at.deny
+    register_test retvalshouldbe 1
+    register_test contain "/etc/cron.deny exists"
+    register_test contain "/etc/at.deny exists"
+    run noncompliant /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+
+    describe correcting situation
+    sed  -i 's/audit/enabled/' /opt/debian-cis/etc/conf.d/"${script}".cfg
+    /opt/debian-cis/bin/hardening/"${script}".sh --apply || true
+
+    touch /etc/cron.allow /etc/at.allow
+    describe Tests purposely failing
+    useradd $test_user
+    chown $test_user:$test_user /etc/cron.allow
+    chown $test_user:$test_user /etc/at.allow
+    register_test retvalshouldbe 1
+    register_test contain "/etc/cron.allow ownership was not set to"
+    register_test contain "/etc/at.allow ownership was not set to"
+    run noncompliant /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+    userdel $test_user
+
+    describe correcting situation
+    sed  -i 's/audit/enabled/' /opt/debian-cis/etc/conf.d/"${script}".cfg
+    /opt/debian-cis/bin/hardening/"${script}".sh --apply || true
+
+    describe Tests purposely failing
+    useradd $test_user
+    chmod 777 /etc/cron.allow
+    chmod 777 /etc/at.allow
+    register_test retvalshouldbe 1
+    register_test contain "/etc/cron.allow permissions were not set to"
+    register_test contain "/etc/at.allow permissions were not set to"
+    run noncompliant /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+    userdel $test_user
+
+    describe correcting situation
+    sed  -i 's/audit/enabled/' /opt/debian-cis/etc/conf.d/"${script}".cfg
+    /opt/debian-cis/bin/hardening/"${script}".sh --apply || true
+
+    describe Checking resolved state
+    register_test retvalshouldbe 0
+    register_test contain "/etc/cron.allow has correct permissions"
+    register_test contain "/etc/cron.allow has correct ownership"
+    register_test contain "/etc/at.allow has correct permissions"
+    register_test contain "/etc/at.allow has correct ownership"
+    run resolved /opt/debian-cis/bin/hardening/"${script}".sh --audit-all
+
 }