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nessusThis script is Copyright (C) 2019-2021 and is owned by Tenable, Inc. or an Affiliate thereof.NEWSTART_CGSL_NS-SA-2019-0139_OPENSSH.NASL
HistoryAug 12, 2019 - 12:00 a.m.

NewStart CGSL MAIN 4.05 : openssh Multiple Vulnerabilities (NS-SA-2019-0139)

2019-08-1200:00:00
This script is Copyright (C) 2019-2021 and is owned by Tenable, Inc. or an Affiliate thereof.
www.tenable.com
14

The remote NewStart CGSL host, running version MAIN 4.05, has openssh packages installed that are affected by multiple vulnerabilities:

  • A covert timing channel flaw was found in the way OpenSSH handled authentication of non-existent users. A remote unauthenticated attacker could possibly use this flaw to determine valid user names by measuring the timing of server responses. (CVE-2016-6210)

  • It was discovered that the OpenSSH sshd daemon fetched PAM environment settings before running the login program. In configurations with UseLogin=yes and the pam_env PAM module configured to read user environment settings, a local user could use this flaw to execute arbitrary code as root. (CVE-2015-8325)

Note that Nessus has not tested for this issue but has instead relied only on the application’s self-reported version number.

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

# The descriptive text and package checks in this plugin were
# extracted from ZTE advisory NS-SA-2019-0139. The text
# itself is copyright (C) ZTE, Inc.

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

if (description)
{
  script_id(127401);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/14");

  script_cve_id("CVE-2015-8325", "CVE-2016-6210");

  script_name(english:"NewStart CGSL MAIN 4.05 : openssh Multiple Vulnerabilities (NS-SA-2019-0139)");

  script_set_attribute(attribute:"synopsis", value:
"The remote machine is affected by multiple vulnerabilities.");
  script_set_attribute(attribute:"description", value:
"The remote NewStart CGSL host, running version MAIN 4.05, has openssh packages installed that are affected by multiple
vulnerabilities:

  - A covert timing channel flaw was found in the way
    OpenSSH handled authentication of non-existent users. A
    remote unauthenticated attacker could possibly use this
    flaw to determine valid user names by measuring the
    timing of server responses. (CVE-2016-6210)

  - It was discovered that the OpenSSH sshd daemon fetched
    PAM environment settings before running the login
    program. In configurations with UseLogin=yes and the
    pam_env PAM module configured to read user environment
    settings, a local user could use this flaw to execute
    arbitrary code as root. (CVE-2015-8325)

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-2019-0139");
  script_set_attribute(attribute:"solution", value:
"Upgrade the vulnerable CGSL openssh packages. Note that updated packages may not be available yet. Please contact ZTE
for more information.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  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:L/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-2015-8325");
  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:"2016/05/01");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/07/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/08/12");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2019-2021 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("audit.inc");
include("global_settings.inc");
include("rpm.inc");

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

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 4.05")
  audit(AUDIT_OS_NOT, 'NewStart CGSL MAIN 4.05');

if (!get_kb_item("Host/ZTE-CGSL/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);

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);

flag = 0;

pkgs = {
  "CGSL MAIN 4.05": [
    "openssh-5.3p1-123.el6_9.cgsl7731",
    "openssh-askpass-5.3p1-123.el6_9.cgsl7731",
    "openssh-clients-5.3p1-123.el6_9.cgsl7731",
    "openssh-debuginfo-5.3p1-123.el6_9.cgsl7731",
    "openssh-ldap-5.3p1-123.el6_9.cgsl7731",
    "openssh-server-5.3p1-123.el6_9.cgsl7731",
    "pam_ssh_agent_auth-0.9.3-123.el6_9.cgsl7731"
  ]
};
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
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "openssh");
}