Linux Distros Unpatched Vulnerability : CVE-2020-11741

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(256874);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/08/27");

  script_cve_id("CVE-2020-11741");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2020-11741");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - An issue was discovered in xenoprof in Xen through 4.13.x, allowing guest OS users (with active profiling)
    to obtain sensitive information about other guests, cause a denial of service, or possibly gain
    privileges. For guests for which active profiling was enabled by the administrator, the xenoprof code
    uses the standard Xen shared ring structure. Unfortunately, this code did not treat the guest as a
    potential adversary: it trusts the guest not to modify buffer size information or modify head / tail
    pointers in unexpected ways. This can crash the host (DoS). Privilege escalation cannot be ruled out.
    (CVE-2020-11741)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2020-11741");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-11741");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/12/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/08/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:xen");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2025 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Ubuntu Linux-16.04", "Host/OS/Ubuntu Linux-18.04");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "libxen-4.6"},
          {"reference": "libxen-dev"},
          {"reference": "libxenstore3.0"},
          {"reference": "xen-hypervisor-4.4-amd64"},
          {"reference": "xen-hypervisor-4.4-arm64"},
          {"reference": "xen-hypervisor-4.4-armhf"},
          {"reference": "xen-hypervisor-4.5-amd64"},
          {"reference": "xen-hypervisor-4.5-arm64"},
          {"reference": "xen-hypervisor-4.5-armhf"},
          {"reference": "xen-hypervisor-4.6-amd64"},
          {"reference": "xen-hypervisor-4.6-arm64"},
          {"reference": "xen-hypervisor-4.6-armhf"},
          {"reference": "xen-system-amd64"},
          {"reference": "xen-system-arm64"},
          {"reference": "xen-system-armhf"},
          {"reference": "xen-utils-4.6"},
          {"reference": "xen-utils-common"},
          {"reference": "xenstore-utils"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "libxen-4.9"},
          {"reference": "libxen-dev"},
          {"reference": "libxenstore3.0"},
          {"reference": "xen-hypervisor-4.6-amd64"},
          {"reference": "xen-hypervisor-4.6-arm64"},
          {"reference": "xen-hypervisor-4.6-armhf"},
          {"reference": "xen-hypervisor-4.7-amd64"},
          {"reference": "xen-hypervisor-4.7-arm64"},
          {"reference": "xen-hypervisor-4.7-armhf"},
          {"reference": "xen-hypervisor-4.8-amd64"},
          {"reference": "xen-hypervisor-4.8-arm64"},
          {"reference": "xen-hypervisor-4.8-armhf"},
          {"reference": "xen-hypervisor-4.9-amd64"},
          {"reference": "xen-hypervisor-4.9-arm64"},
          {"reference": "xen-hypervisor-4.9-armhf"},
          {"reference": "xen-system-amd64"},
          {"reference": "xen-system-arm64"},
          {"reference": "xen-system-armhf"},
          {"reference": "xen-utils-4.9"},
          {"reference": "xen-utils-common"},
          {"reference": "xenstore-utils"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');
var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}