Do Not Enable the NFS Service

# SPDX-FileCopyrightText: 2025 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

# ------------------------------------------------------------------
# METADATA
# ------------------------------------------------------------------

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.130457");
  script_version("2025-11-21T05:40:28+0000");
  script_tag(name:"last_modification", value:"2025-11-21 05:40:28 +0000 (Fri, 21 Nov 2025)");
  script_tag(name:"creation_date", value:"2025-05-07 11:45:56 +0000 (Wed, 07 May 2025)");
  script_tag(name:"cvss_base", value:"0.0");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:H/Au:S/C:N/I:N/A:N");
  script_tag(name:"qod", value:"97");

  script_name("Do Not Enable the NFS Service");

  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2025 Greenbone AG");
  script_family("Policy");
  script_dependencies("compliance_tests.nasl", "compliance_os_check.nasl");

  script_mandatory_keys("Compliance/Launch", "policy/ssh/login/euleros_eulerosvirtual_openeuler_hce");

  script_xref(name:"Policy", value:"EulerOS Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.22 Do Not Enable the NFS Service (Recommendation)");
  script_xref(name:"Policy", value:"EulerOS Virtual: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.22 Do Not Enable the NFS Service (Recommendation)");
  script_xref(name:"Policy", value:"HCE Linux (Huawei Cloud EulerOS): openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.22 Do Not Enable the NFS Service (Recommendation)");
  script_xref(name:"Policy", value:"openEuler Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.2 Software: 1.2.22 Do Not Enable the NFS Service (Recommendation)");

  script_tag(name:"summary", value:"The Network File System (NFS) is one of the earliest and most
widely used file systems in UNIX environments. It allows a system to mount file systems of other
servers over the network. If the system does not share content through NFS, you are advised to
disable NFS to reduce the remote attack surface.");

  exit(0);
}

include("ssh_func.inc");
include("host_details.inc");
include("policy_reporting_module.inc");

title = "Do Not Enable the NFS Service";

solution = "Disable the nfs-server service on a server where the NFS component has been installed:

# systemctl --now disable nfs-server";

check_type = "SSH_Cmd";

action = 'Run the command in the terminal:
# systemctl is-enabled nfs-server';

expected_value = 'The output should be equal to "disabled" or be equal to "not-found" or contain "Failed to get unit file state"';

# ------------------------------------------------------------------
# CONNECTION CHECK
# ------------------------------------------------------------------

if(!get_kb_item("login/SSH/success") || !sock = ssh_login_or_reuse_connection()){

  report_ssh_error(title: title,
                   solution: solution,
                   action: action,
                   expected_value: expected_value,
                   check_type: check_type);
  exit(0);
}

# ------------------------------------------------------------------
# CHECK : Verify command `systemctl is-enabled nfs-server`
# ------------------------------------------------------------------

step_cmd = 'systemctl is-enabled nfs-server';
actual_value = ssh_cmd(socket:sock, cmd:step_cmd, return_errors:TRUE, return_linux_errors_only:TRUE);

if(eregmatch(string: actual_value, pattern:"(No such file or directory|Permission denied|Command not found|Segmentation fault|service not found|is not running|syntax error near unexpected token|syntax error: unexpected end of file)", icase: TRUE)){
  compliant = "incomplete";
  comment = "Something went wrong during the audit check. Please try again.";
}else if(actual_value == 'disabled' || actual_value == 'not-found' || strstr(actual_value, 'Failed to get unit file state')){
  compliant = "yes";
  comment = "Check passed";
}else{
  compliant = "no";
  comment = "Check failed";
}

# ------------------------------------------------------------------
# REPORT
# ------------------------------------------------------------------

target = get_kb_item("policy/ssh/login/os-release");
comment = "Target: " + target + "\n" + comment;

report_audit(action: action,
             actual_value: actual_value,
             expected_value: expected_value,
             is_compliant: compliant,
             solution: solution,
             check_type: check_type,
             title: title,
             comment: comment);

exit(0);