NewStart CGSL CORE 5.05 / MAIN 5.05 : libX11 Vulnerability (NS-SA-2022-0042)

##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from ZTE advisory NS-SA-2022-0042. The text
# itself is copyright (C) ZTE, Inc.
##

include('compat.inc');

if (description)
{
  script_id(160836);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/05/10");

  script_cve_id("CVE-2021-31535");

  script_name(english:"NewStart CGSL CORE 5.05 / MAIN 5.05 : libX11 Vulnerability (NS-SA-2022-0042)");

  script_set_attribute(attribute:"synopsis", value:
"The remote NewStart CGSL host is affected by a vulnerability.");
  script_set_attribute(attribute:"description", value:
"The remote NewStart CGSL host, running version CORE 5.05 / MAIN 5.05, has libX11 packages installed that are affected by
a vulnerability:

  - LookupCol.c in X.Org X through X11R7.7 and libX11 before 1.7.1 might allow remote attackers to execute
    arbitrary code. The libX11 XLookupColor request (intended for server-side color lookup) contains a flaw
    allowing a client to send color-name requests with a name longer than the maximum size allowed by the
    protocol (and also longer than the maximum packet size for normal-sized packets). The user-controlled data
    exceeding the maximum size is then interpreted by the server as additional X protocol requests and
    executed, e.g., to disable X server authorization completely. For example, if the victim encounters
    malicious terminal control sequences for color codes, then the attacker may be able to take full control
    of the running graphical session. (CVE-2021-31535)

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:"http://security.gd-linux.com/notice/NS-SA-2022-0042");
  script_set_attribute(attribute:"see_also", value:"http://security.gd-linux.com/info/CVE-2021-31535");
  script_set_attribute(attribute:"solution", value:
"Upgrade the vulnerable CGSL libX11 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:POC/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:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-31535");

  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:"2021/05/27");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/05/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2022/05/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_core:libX11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_core:libX11-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_core:libX11-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_core:libX11-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libX11");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libX11-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libX11-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:zte:cgsl_main:libX11-devel");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:zte:cgsl_core:5");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:zte:cgsl_main:5");
  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 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 CORE 5.05" &&
    release !~ "CGSL MAIN 5.05")
  audit(AUDIT_OS_NOT, 'NewStart CGSL CORE 5.05 / NewStart CGSL MAIN 5.05');

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 CORE 5.05': [
    'libX11-1.6.7-4.el7_9',
    'libX11-common-1.6.7-4.el7_9',
    'libX11-debuginfo-1.6.7-4.el7_9',
    'libX11-devel-1.6.7-4.el7_9'
  ],
  'CGSL MAIN 5.05': [
    'libX11-1.6.7-4.el7_9',
    'libX11-common-1.6.7-4.el7_9',
    'libX11-debuginfo-1.6.7-4.el7_9',
    'libX11-devel-1.6.7-4.el7_9'
  ]
};
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, 'libX11');
}