NewStart CGSL MAIN 6.02 : libxml2 Multiple Vulnerabilities (NS-SA-2022-0050)

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from ZTE advisory NS-SA-2022-0050. The text
# itself is copyright (C) ZTE, Inc.
##

include('compat.inc');

if (description)
{
  script_id(160750);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/11/01");

  script_cve_id(
    "CVE-2020-24977",
    "CVE-2021-3516",
    "CVE-2021-3517",
    "CVE-2021-3518",
    "CVE-2021-3537",
    "CVE-2021-3541"
  );
  script_xref(name:"IAVA", value:"2022-A-0038");
  script_xref(name:"IAVA", value:"2021-A-0482");
  script_xref(name:"IAVA", value:"2022-A-0165");
  script_xref(name:"IAVA", value:"2021-A-0487-S");

  script_name(english:"NewStart CGSL MAIN 6.02 : libxml2 Multiple Vulnerabilities (NS-SA-2022-0050)");

  script_set_attribute(attribute:"synopsis", value:
"The remote NewStart CGSL host is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The remote NewStart CGSL host, running version MAIN 6.02, has libxml2 packages installed that are affected by multiple
vulnerabilities:

  - GNOME project libxml2 v2.9.10 has a global buffer over-read vulnerability in xmlEncodeEntitiesInternal at
    libxml2/entities.c. The issue has been fixed in commit 50f06b3e. (CVE-2020-24977)

  - There's a flaw in libxml2's xmllint in versions before 2.9.11. An attacker who is able to submit a crafted
    file to be processed by xmllint could trigger a use-after-free. The greatest impact of this flaw is to
    confidentiality, integrity, and availability. (CVE-2021-3516)

  - There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2.9.11. An attacker
    who is able to supply a crafted file to be processed by an application linked with the affected
    functionality of libxml2 could trigger an out-of-bounds read. The most likely impact of this flaw is to
    application availability, with some potential impact to confidentiality and integrity if an attacker is
    able to use memory information to further exploit the application. (CVE-2021-3517)

  - There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to submit a crafted file to
    be processed by an application linked with libxml2 could trigger a use-after-free. The greatest impact
    from this flaw is to confidentiality, integrity, and availability. (CVE-2021-3518)

  - A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while
    parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery
    mode and post-validated, the flaw could be used to crash the application. The highest threat from this
    vulnerability is to system availability. (CVE-2021-3537)

  - A flaw was found in libxml2. Exponential entity expansion attack its possible bypassing all existing
    protection mechanisms and leading to denial of service. (CVE-2021-3541)

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:"http://security.gd-linux.com/notice/NS-SA-2022-0050");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2020-24977");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-3516");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-3517");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-3518");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-3537");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-3541");
  script_set_attribute(attribute:"solution", value:
"Upgrade the vulnerable CGSL libxml2 packages. Note that updated packages may not be available yet. Please contact ZTE
for more information.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:F/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-3517");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2021-3518");

  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:"2020/09/04");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/05/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/05/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libxml2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libxml2-debugsource");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libxml2-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libxml2-static");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:python3-libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:python3-libxml2-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:zte:cgsl_main:6");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2022-2023 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/ZTE-CGSL/release", "Host/ZTE-CGSL/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/ZTE-CGSL/release');
if (isnull(release) || release !~ "^CGSL (MAIN|CORE)") audit(AUDIT_OS_NOT, 'NewStart Carrier Grade Server Linux');

if (release !~ "CGSL MAIN 6.02")
  audit(AUDIT_OS_NOT, 'NewStart CGSL MAIN 6.02');

if (!get_kb_item('Host/ZTE-CGSL/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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'NewStart Carrier Grade Server Linux', cpu);

var flag = 0;

var pkgs = {
  'CGSL MAIN 6.02': [
    'libxml2-2.9.7-9.el8_4.2',
    'libxml2-debuginfo-2.9.7-9.el8_4.2',
    'libxml2-debugsource-2.9.7-9.el8_4.2',
    'libxml2-devel-2.9.7-9.el8_4.2',
    'libxml2-static-2.9.7-9.el8_4.2',
    'python3-libxml2-2.9.7-9.el8_4.2',
    'python3-libxml2-debuginfo-2.9.7-9.el8_4.2'
  ]
};
var pkg_list = pkgs[release];

foreach (pkg in pkg_list)
  if (rpm_check(release:'ZTE ' + release, 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, 'libxml2');
}