Debian dla-3813 : shim-helpers-amd64-signed-template - security update

#%NASL_MIN_LEVEL 80900
#
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory dla-3813. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(196989);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/05/14");

  script_cve_id(
    "CVE-2023-40546",
    "CVE-2023-40547",
    "CVE-2023-40548",
    "CVE-2023-40549",
    "CVE-2023-40550",
    "CVE-2023-40551"
  );

  script_name(english:"Debian dla-3813 : shim-helpers-amd64-signed-template - security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing one or more security-related updates.");
  script_set_attribute(attribute:"description", value:
"The remote Debian 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the
dla-3813 advisory.

  - A flaw was found in Shim when an error happened while creating a new ESL variable. If Shim fails to create
    the new variable, it tries to print an error message to the user; however, the number of parameters used
    by the logging function doesn't match the format string used by it, leading to a crash under certain
    circumstances. (CVE-2023-40546)

  - A remote code execution vulnerability was found in Shim. The Shim boot support trusts attacker-controlled
    values when parsing an HTTP response. This flaw allows an attacker to craft a specific malicious HTTP
    request, leading to a completely controlled out-of-bounds write primitive and complete system compromise.
    This flaw is only exploitable during the early boot phase, an attacker needs to perform a Man-in-the-
    Middle or compromise the boot server to be able to exploit this vulnerability successfully.
    (CVE-2023-40547)

  - A buffer overflow was found in Shim in the 32-bit system. The overflow happens due to an addition
    operation involving a user-controlled value parsed from the PE binary being used by Shim. This value is
    further used for memory allocation operations, leading to a heap-based buffer overflow. This flaw causes
    memory corruption and can lead to a crash or data integrity issues during the boot phase. (CVE-2023-40548)

  - An out-of-bounds read flaw was found in Shim due to the lack of proper boundary verification during the
    load of a PE binary. This flaw allows an attacker to load a crafted PE binary, triggering the issue and
    crashing Shim, resulting in a denial of service. (CVE-2023-40549)

  - An out-of-bounds read flaw was found in Shim when it tried to validate the SBAT information. This issue
    may expose sensitive data during the system's boot phase. (CVE-2023-40550)

  - A flaw was found in the MZ binary format in Shim. An out-of-bounds read may occur, leading to a crash or
    possible exposure of sensitive data during the system's boot phase. (CVE-2023-40551)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/source-package/shim");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40546");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40547");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40548");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40549");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40550");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2023-40551");
  script_set_attribute(attribute:"see_also", value:"https://packages.debian.org/source/buster/shim");
  script_set_attribute(attribute:"solution", value:
"Upgrade the shim-helpers-amd64-signed-template packages.");
  script_set_cvss_base_vector("CVSS2#AV:A/AC:H/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:A/AC:H/PR:N/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-2023-40547");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2023/12/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/05/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/05/14");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:shim-helpers-amd64-signed-template");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:shim-helpers-arm64-signed-template");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:shim-helpers-i386-signed-template");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:shim-unsigned");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:10.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Debian Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}

include('debian_package.inc');

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);

var debian_release = get_kb_item('Host/Debian/release');
if ( isnull(debian_release) ) audit(AUDIT_OS_NOT, 'Debian');
debian_release = chomp(debian_release);
if (! preg(pattern:"^(10)\.[0-9]+", string:debian_release)) audit(AUDIT_OS_NOT, 'Debian 10.0', 'Debian ' + debian_release);
var cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Debian', cpu);

var pkgs = [
    {'release': '10.0', 'prefix': 'shim-helpers-amd64-signed-template', 'reference': '15.8-1~deb10u1'},
    {'release': '10.0', 'prefix': 'shim-helpers-arm64-signed-template', 'reference': '15.8-1~deb10u1'},
    {'release': '10.0', 'prefix': 'shim-helpers-i386-signed-template', 'reference': '15.8-1~deb10u1'},
    {'release': '10.0', 'prefix': 'shim-unsigned', 'reference': '15.8-1~deb10u1'}
];

var flag = 0;
foreach package_array ( pkgs ) {
  var _release = NULL;
  var prefix = NULL;
  var reference = NULL;
  if (!empty_or_null(package_array['release'])) _release = package_array['release'];
  if (!empty_or_null(package_array['prefix'])) prefix = package_array['prefix'];
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (_release && prefix && reference) {
    if (deb_check(release:_release, prefix:prefix, reference:reference)) flag++;
  }
}

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : deb_report_get()
  );
  exit(0);
}
else
{
  var tested = deb_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'shim-helpers-amd64-signed-template / etc');
}