Microsoft PowerShell Core Denial of Service Vulnerability - Linux

# SPDX-FileCopyrightText: 2018 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

CPE = "cpe:/a:microsoft:powershell";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.813041");
  script_version("2025-09-19T15:40:40+0000");
  script_cve_id("CVE-2018-0875");
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_tag(name:"last_modification", value:"2025-09-19 15:40:40 +0000 (Fri, 19 Sep 2025)");
  script_tag(name:"severity_vector", value:"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-08-24 17:37:00 +0000 (Mon, 24 Aug 2020)");
  script_tag(name:"creation_date", value:"2018-03-16 11:09:04 +0530 (Fri, 16 Mar 2018)");
  script_name("Microsoft PowerShell Core Denial of Service Vulnerability - Linux");

  script_tag(name:"summary", value:"This host is missing an important security
  update for PowerShell Core according to Microsoft security update March 2018.");

  script_tag(name:"vuldetect", value:"Checks if a vulnerable version is present on the target host.");

  script_tag(name:"insight", value:"The flaw exists when .NET Core improperly
  handles specially crafted requests causing a hash collision.");

  script_tag(name:"impact", value:"Successful exploitation will allow attackers
  to cause performance degrade resulting in a denial of service condition.");

  script_tag(name:"affected", value:"PowerShell Core version 6.0.0 before 6.0.2 on Linux.");

  script_tag(name:"solution", value:"Update PowerShell Core to version 6.0.2 or later.");

  script_tag(name:"solution_type", value:"VendorFix");
  script_tag(name:"qod_type", value:"executable_version");
  script_xref(name:"URL", value:"https://github.com/PowerShell/PowerShell/issues/6401");
  script_xref(name:"URL", value:"http://www.securityfocus.com/bid/103225");
  script_xref(name:"URL", value:"https://github.com/PowerShell/PowerShell/releases/tag/v6.0.2");
  script_xref(name:"URL", value:"https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2018-0875");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2018 Greenbone AG");
  script_family("Denial of Service");
  script_dependencies("gb_powershell_core_detect_lin.nasl");
  script_mandatory_keys("PowerShell/Linux/Ver");
  exit(0);
}

include("version_func.inc");
include("host_details.inc");

if(!infos = get_app_version_and_location(cpe:CPE, exit_no_version:TRUE)) exit(0);
psVer = infos["version"];
psPath = infos["location"];

if(psVer =~ "^(6\.0)" && version_is_less(version:psVer, test_version:"6.0.2"))
{
  report = report_fixed_ver(installed_version:psVer, fixed_version:"6.0.2", install_path:psPath);
  security_message(data:report);
  exit(0);
}
exit(0);