EulerOS Virtualization 3.0.2.6 : PyYAML (EulerOS-SA-2021-2902)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
##

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(156538);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/01/06");

  script_cve_id("CVE-2020-14343");
  script_xref(name:"IAVA", value:"2021-A-0463");

  script_name(english:"EulerOS Virtualization 3.0.2.6 : PyYAML (EulerOS-SA-2021-2902)");

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

  - A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to
    arbitrary code execution when it processes untrusted YAML files through the full_load method or with the
    FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this
    flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the
    python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747. (CVE-2020-14343)

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-2021-2902
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?328d84bd");
  script_set_attribute(attribute:"solution", value:
"Update the affected PyYAML packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/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:N/AC:L/PR:N/UI:N/S:U/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-2020-14343");

  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:"2021/01/21");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/12/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/01/06");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:huawei:euleros:PyYAML");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:huawei:euleros:uvp:3.0.2.6");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022 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("audit.inc");
include("global_settings.inc");
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 != "3.0.2.6") audit(AUDIT_OS_NOT, "EulerOS Virtualization 3.0.2.6");
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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "EulerOS", cpu);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_ARCH_NOT, "i686 / x86_64", cpu);

var flag = 0;

var pkgs = [
  "PyYAML-3.10-11.h5.eulerosv2r7"
];

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

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    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, "PyYAML");
}