diff --git a/script/check/host/all/core_ssh_config_access_restriction.check.sh b/script/check/host/all/core_ssh_config_access_restriction.check.sh
new file mode 100755
index 0000000..a9eeb6d
--- /dev/null
+++ b/script/check/host/all/core_ssh_config_access_restriction.check.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+
+_CURRENT_FILE='/etc/ssh/sshd_config.d/AccessRestriction.conf'
+
+#No file is NOT ok
+[ ! -e "${_CURRENT_FILE}" ] \
+    && exit 1
+
+#File has to be readable, then
+#search for '/definitions/' in the path of current file, after readlink expanded a potential symlink.
+[ -r "${_CURRENT_FILE}" ] \
+    && readlink -f "${_CURRENT_FILE}" | grep -q "/definitions/" \
+    && exit 0
+
+#File has to be readable, then
+#search for '/core/default/' in the path of current file, after readlink expanded a potential symlink.
+[ -r "${_CURRENT_FILE}" ] \
+    && readlink -f "${_CURRENT_FILE}" | grep -q "/core/default/" \
+    && exit 0
+
+exit 1
diff --git a/script/check/host/all/core_sudoers_file_of_jenkins_points_to_definitions.check.sh b/script/check/host/all/core_sudoers_file_of_jenkins_points_to_definitions.check.sh
index 5e0e97e..f9b7cdd 100755
--- a/script/check/host/all/core_sudoers_file_of_jenkins_points_to_definitions.check.sh
+++ b/script/check/host/all/core_sudoers_file_of_jenkins_points_to_definitions.check.sh
@@ -12,4 +12,10 @@ _CURRENT_FILE='/etc/sudoers.d/allow-jenkins-updateRepositories'
     && readlink -f "${_CURRENT_FILE}" | grep -q "/definitions/" \
     && exit 0
 
+#File has to be readable, then
+#search for '/core/default/' in the path of current file, after readlink expanded a potential symlink.
+[ -r "${_CURRENT_FILE}" ] \
+    && readlink -f "${_CURRENT_FILE}" | grep -q "/core/default/" \
+    && exit 0
+
 exit 1
diff --git a/script/check/host/all/core_user_name_may_contain_dots.check.sh b/script/check/host/all/core_user_name_may_contain_dots.check.sh
new file mode 100755
index 0000000..683dcc9
--- /dev/null
+++ b/script/check/host/all/core_user_name_may_contain_dots.check.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+_FILE_NAME='/etc/adduser.conf'
+
+# The first expression should filter the line conaining the key.
+#   - here a regular expression (-E) is used to enforce the line starts with the key.
+# Second expression looks for the uninterpreted fix string (-F), but without output.
+grep -E '^NAME_REGEX=.*$' "${_FILE_NAME}" | grep -q -F '^[a-z][-a-z0-9_.]*\$?$' 2> /dev/null \
+    && exit 0
+
+exit 1