Avoid Using USB Storage

# 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("1.3.6.1.4.1.25623.1.0.130420");
  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 11:45:55 +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("Avoid Using USB Storage");

  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");

  script_xref(name:"Policy", value:"EulerOS Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.1 File Systems: 1.1.17 Avoid Using USB Storage (Recommendation)");
  script_xref(name:"Policy", value:"EulerOS Virtual: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.1 File Systems: 1.1.17 Avoid Using USB Storage (Recommendation)");
  script_xref(name:"Policy", value:"openEuler Baseline: openEuler Security Configuration Baseline (v1.0.0): 1. Initial deployment: 1.1 File Systems: 1.1.17 Avoid Using USB Storage (Recommendation)");

  script_tag(name:"summary", value:"USB storage devices are usually used to transfer data between
servers. However, in most cases, data on USB storage devices cannot be protected by technical
methods, thereby increasing the risk of attacks. Viruses and Trojan horses on USB devices may
infect and damage the server. If the USB storage devices are not properly managed, data leakage may
occur. Therefore, an attacker can construct or damage data on a USB storage device. When an
authorized administrator operates the USB storage device on a server, the server is attacked and
data is stolen. You are advised to disable USB storage as required.");

  exit(0);
}

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

title = "Avoid Using USB Storage";

solution = "In the /etc/modprobe.d/ directory, add a configuration file with any file name with
the suffix <quote>.conf<quote>. The owner and owner group are both root, and the permission is 600. Enter the
code in the following format to disable USB storage:

# vim /etc/modprobe.d/test.conf
install usb-storage /bin/true";

check_type = "SSH_Cmd";

action = 'Run the command in the terminal:
# modprobe -n -v usb-storage';

expected_value = 'The output should be equal to "install /bin/true"';

# ------------------------------------------------------------------
# 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 `modprobe -n -v usb-storage`
# ------------------------------------------------------------------

step_cmd = 'modprobe -n -v usb-storage';
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 == 'install /bin/true'){
  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);