EulerOS Virtualization 2.11.0 : grub2 (EulerOS-SA-2023-2095)

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

include('compat.inc');

if (description)
{
  script_id(176842);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/06/07");

  script_cve_id("CVE-2021-3981", "CVE-2022-2601", "CVE-2022-3775");

  script_name(english:"EulerOS Virtualization 2.11.0 : grub2 (EulerOS-SA-2023-2095)");

  script_set_attribute(attribute:"synopsis", value:
"The remote EulerOS Virtualization host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"According to the versions of the grub2 packages installed, the EulerOS Virtualization installation on the remote host is
affected by the following vulnerabilities :

  - A flaw in grub2 was found where its configuration file, known as grub.cfg, is being created with the wrong
    permission set allowing non privileged users to read its content. This represents a low severity
    confidentiality issue, as those users can eventually read any encrypted passwords present in grub.cfg.
    This flaw affects grub2 2.06 and previous versions. This issue has been fixed in grub upstream but no
    version with the fix is currently released. (CVE-2021-3981)

  - A buffer overflow was found in grub_font_construct_glyph(). A malicious crafted pf2 font can lead to an
    overflow when calculating the max_glyph_size value, allocating a smaller than needed buffer for the glyph,
    this further leads to a buffer overflow and a heap based out-of-bounds write. An attacker may use this
    vulnerability to circumvent the secure boot mechanism. (CVE-2022-2601)

  - When rendering certain unicode sequences, grub2's font code doesn't proper validate if the informed
    glyph's width and height is constrained within bitmap size. As consequence an attacker can craft an input
    which will lead to a out-of-bounds write into grub2's heap, leading to memory corruption and availability
    issues. Although complex, arbitrary code execution could not be discarded. (CVE-2022-3775)

Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security
advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional
issues.");
  # https://developer.huaweicloud.com/ict/en/site-euleros/euleros/security-advisories/EulerOS-SA-2023-2095
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?b28aa61b");
  script_set_attribute(attribute:"solution", value:
"Update the affected grub2 packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-3981");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2022-2601");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/07/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/06/06");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/06/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-efi-x64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-efi-x64-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-pc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-pc-modules");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-tools-efi");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-tools-extra");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:grub2-tools-minimal");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:uvp:2.11.0");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/cpu", "Host/EulerOS/release", "Host/EulerOS/rpm-list", "Host/EulerOS/uvp_version");

  exit(0);
}

include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var _release = get_kb_item("Host/EulerOS/release");
if (isnull(_release) || _release !~ "^EulerOS") audit(AUDIT_OS_NOT, "EulerOS");
var uvp = get_kb_item("Host/EulerOS/uvp_version");
if (uvp != "2.11.0") audit(AUDIT_OS_NOT, "EulerOS Virtualization 2.11.0");
if (!get_kb_item("Host/EulerOS/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

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 && "x86" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);

var flag = 0;

var pkgs = [
  "grub2-common-2.06-3.h19.eulerosv2r11",
  "grub2-efi-x64-2.06-3.h19.eulerosv2r11",
  "grub2-efi-x64-modules-2.06-3.h19.eulerosv2r11",
  "grub2-pc-2.06-3.h19.eulerosv2r11",
  "grub2-pc-modules-2.06-3.h19.eulerosv2r11",
  "grub2-tools-2.06-3.h19.eulerosv2r11",
  "grub2-tools-efi-2.06-3.h19.eulerosv2r11",
  "grub2-tools-extra-2.06-3.h19.eulerosv2r11",
  "grub2-tools-minimal-2.06-3.h19.eulerosv2r11"
];

foreach (var pkg in pkgs)
  if (rpm_check(release:"EulerOS-2.0", reference:pkg)) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  var tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "grub2");
}