Azure Linux 3.0 Security Update: edk2 / openssl (CVE-2022-0778)

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

include('compat.inc');

if (description)
{
  script_id(215912);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2025/09/15");

  script_cve_id("CVE-2022-0778");
  script_xref(name:"IAVA", value:"2022-A-0121-S");

  script_name(english:"Azure Linux 3.0 Security Update: edk2 / openssl (CVE-2022-0778)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Azure Linux host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The version of edk2 / openssl installed on the remote Azure Linux 3.0 host is prior to tested version. It is, therefore,
affected by a vulnerability as referenced in the CVE-2022-0778 advisory.

  - The BN_mod_sqrt() function, which computes a modular square root, contains a bug that can cause it to loop
    forever for non-prime moduli. Internally this function is used when parsing certificates that contain
    elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point
    encoded in compressed form. It is possible to trigger the infinite loop by crafting a certificate that has
    invalid explicit curve parameters. Since certificate parsing happens prior to verification of the
    certificate signature, any process that parses an externally supplied certificate May thus be subject to a
    denial of service attack. The infinite loop can also be reached when parsing crafted private keys as they
    can contain explicit elliptic curve parameters. Thus vulnerable situations include: - TLS clients
    consuming server certificates - TLS servers consuming client certificates - Hosting providers taking
    certificates or private keys from customers - Certificate authorities parsing certification requests from
    subscribers - Anything else which parses ASN.1 elliptic curve parameters Also any other applications that
    use the BN_mod_sqrt() where the attacker can control the parameter values are vulnerable to this DoS
    issue. In the OpenSSL 1.0.2 version the public key is not parsed during initial parsing of the certificate
    which makes it slightly harder to trigger the infinite loop. However any operation which requires the
    public key from the certificate will trigger the infinite loop. In particular the attacker can use a self-
    signed certificate to trigger the loop during verification of the certificate signature. This issue
    affects OpenSSL versions 1.0.2, 1.1.1 and 3.0. It was addressed in the releases of 1.1.1n and 3.0.2 on the
    15th March 2022. Fixed in OpenSSL 3.0.2 (Affected 3.0.0,3.0.1). Fixed in OpenSSL 1.1.1n (Affected
    1.1.1-1.1.1m). Fixed in OpenSSL 1.0.2zd (Affected 1.0.2-1.0.2zc). (CVE-2022-0778)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2022-0778");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-2022-0778");

  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:"2022/03/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/09/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/02/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-experimental");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-ext4");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-ovmf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-ovmf-ia32");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-ovmf-xen");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-tools-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:edk2-tools-python");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl-perl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:microsoft:azure_linux:openssl-static");
  script_set_attribute(attribute:"cpe", value:"x-cpe:/o:microsoft:azure_linux");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  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");
  script_require_keys("Host/local_checks_enabled", "Host/AzureLinux/release", "Host/AzureLinux/rpm-list", "Host/cpu");

  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/AzureLinux/release');
if (isnull(release) || 'Azure Linux' >!< release) audit(AUDIT_OS_NOT, 'Azure Linux');
var os_ver = pregmatch(pattern: "Azure Linux ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Azure Linux');
os_ver = os_ver[1];
if (! preg(pattern:"^3([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Azure Linux 3.0', 'Azure Linux ' + os_ver);

if (!get_kb_item('Host/AzureLinux/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)
  audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Azure Linux', cpu);

var pkgs = [
    {'reference':'edk2-debuginfo-20240223gitedc6681206c1-2.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-experimental-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-ext4-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-ovmf-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-ovmf-ia32-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-ovmf-xen-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-tools-20240223gitedc6681206c1-2.azl3', 'cpu':'x86_64', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-tools-doc-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'edk2-tools-python-20240223gitedc6681206c1-2.azl3', 'release':'3.0', 'rpm_spec_vers_cmp':TRUE}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = NULL;
  var cves = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) _release = 'Azure Linux ' + package_array['release'];
  if (!empty_or_null(package_array['sp'])) sp = package_array['sp'];
  if (!empty_or_null(package_array['cpu'])) _cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (!empty_or_null(package_array['cves'])) cves = package_array['cves'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj, cves:cves)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      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, 'edk2-debuginfo / edk2-experimental / edk2-ext4 / edk2-ovmf / etc');
}