Synology DiskStation Manager (DSM) 6.2.x < 6.2.3-25426-2 Multiple Vulnerabilities (Synology-SA-20:18) - Unreliable Remote Version Check

# SPDX-FileCopyrightText: 2022 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:synology:diskstation_manager";

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.170286");
  script_version("2024-03-15T15:36:48+0000");
  script_tag(name:"last_modification", value:"2024-03-15 15:36:48 +0000 (Fri, 15 Mar 2024)");
  # nb: This was initially a single VT but had to be split into two VTs in 2023. The original date
  # for both (the new and the old one) has been kept in this case.
  script_tag(name:"creation_date", value:"2022-11-21 08:46:21 +0000 (Mon, 21 Nov 2022)");
  script_tag(name:"cvss_base", value:"6.8");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_tag(name:"severity_vector", value:"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H");
  script_tag(name:"severity_origin", value:"NVD");
  script_tag(name:"severity_date", value:"2020-11-09 14:59:00 +0000 (Mon, 09 Nov 2020)");

  script_cve_id("CVE-2020-27650", "CVE-2020-27652", "CVE-2020-27656", "CVE-2020-27648");

  script_tag(name:"qod_type", value:"remote_banner_unreliable");

  script_tag(name:"solution_type", value:"VendorFix");

  script_name("Synology DiskStation Manager (DSM) 6.2.x < 6.2.3-25426-2 Multiple Vulnerabilities (Synology-SA-20:18) - Unreliable Remote Version Check");

  script_category(ACT_GATHER_INFO);

  script_copyright("Copyright (C) 2022 Greenbone AG");
  script_family("General");
  script_dependencies("gb_synology_dsm_consolidation.nasl");
  script_mandatory_keys("synology/dsm/detected");

  script_tag(name:"summary", value:"Synology DiskStation Manager (DSM) is prone to multiple
  vulnerabilities.");

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

  script_tag(name:"insight", value:"The following vulnerabilities exist / mitigation was done:

  - CVE-2020-27650: Synology DiskStation Manager does not set the Secure flag for the session cookie
  in an HTTPS session, which makes it easier for remote attackers to capture this cookie by
  intercepting its transmission within an HTTP session.

  - CVE-2020-27652: Algorithm downgrade vulnerability in QuickConnect allows man-in-the-middle
  attackers to spoof servers and obtain sensitive information via unspecified vectors.

  - CVE-2020-27656: Cleartext transmission of sensitive information vulnerability in DDNS allows
  man-in-the-middle attackers to eavesdrop authentication information of DNSExit via unspecified
  vectors.

  - CVE-2020-27648: Improper certificate validation vulnerability in OpenVPN client allows
  man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted
  certificate.");

  script_tag(name:"affected", value:"Synology DSM version 6.2.x prior to 6.2.3-25426-2.");

  script_tag(name:"solution", value:"Update to firmware version 6.2.3-25426-2 or later.");

  script_xref(name:"URL", value:"https://www.synology.com/en-global/security/advisory/Synology_SA_20_18");

  exit(0);
}

include("host_details.inc");
include("revisions-lib.inc");
include("version_func.inc");

if (!version = get_app_version(cpe: CPE, nofork: TRUE))
  exit(0);

# nb: The patch level version cannot be obtained so when the fix is on a patch level version (e.g.
# 7.2.1-69057-2 and not 7.2.1-69057), there will be 2 VTs with different qod_type.
if (version =~ "^6\.2\.3-25426" && (revcomp(a: version, b: "6.2.3-25426-2") < 0)) {
  report = report_fixed_ver(installed_version: version, fixed_version: "6.2.3-25426-2");
  security_message(port: 0, data: report);
  exit(0);
}

# nb: This is checked by VT 1.3.6.1.4.1.25623.1.0.170240
if (version =~ "^6\.2" && (revcomp(a: version, b: "6.2.3-25426") < 0))
  exit(0);

exit(99);