Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS : nginx vulnerabilities (USN-3812-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3812-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include('compat.inc');

if (description)
{
  script_id(118820);
  script_version("1.11");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id("CVE-2018-16843", "CVE-2018-16844", "CVE-2018-16845");
  script_xref(name:"USN", value:"3812-1");

  script_name(english:"Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS : nginx vulnerabilities (USN-3812-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"The remote Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS host has packages installed that are affected by multiple
vulnerabilities as referenced in the USN-3812-1 advisory.

    It was discovered that nginx incorrectly handled the HTTP/2 implementation. A remote attacker could
    possibly use this issue to cause excessive memory consumption, leading to a denial of service. This issue
    only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 18.10. (CVE-2018-16843)

    Gal Goldshtein discovered that nginx incorrectly handled the HTTP/2 implementation. A remote attacker
    could possibly use this issue to cause excessive CPU usage, leading to a denial of service. This issue
    only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 18.10. (CVE-2018-16844)

    It was discovered that nginx incorrectly handled the ngx_http_mp4_module module. A remote attacker could
    possibly use this issue with a specially crafted mp4 file to cause nginx to crash, stop responding, or
    access arbitrary memory. (CVE-2018-16845)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

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:"https://ubuntu.com/security/notices/USN-3812-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/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-2018-16845");

  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:"2018/11/07");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/11/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/11/08");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-core");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-extras");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-full");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-light");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-naxsi");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx-naxsi-ui");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-auth-pam");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-cache-purge");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-dav-ext");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-echo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-fancyindex");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-geoip");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-headers-more-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-image-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-lua");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-ndk");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-perl");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-subs-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-uploadprogress");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-upstream-fair");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-xslt-filter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-mail");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-nchan");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-rtmp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-stream");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:nginx");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

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

  script_copyright(english:"Ubuntu Security Notice (C) 2018-2024 Canonical, Inc. / NASL script (C) 2018-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}

include('debian_package.inc');

if ( ! get_kb_item('Host/local_checks_enabled') ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
var os_release = get_kb_item('Host/Ubuntu/release');
if ( isnull(os_release) ) audit(AUDIT_OS_NOT, 'Ubuntu');
os_release = chomp(os_release);
if (! ('14.04' >< os_release || '16.04' >< os_release || '18.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 14.04 / 16.04 / 18.04', 'Ubuntu ' + os_release);
if ( ! get_kb_item('Host/Debian/dpkg-l') ) 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$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Ubuntu', cpu);

var pkgs = [
    {'osver': '14.04', 'pkgname': 'nginx', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-common', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-core', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-extras', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-full', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-light', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-naxsi', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '14.04', 'pkgname': 'nginx-naxsi-ui', 'pkgver': '1.4.6-1ubuntu3.9'},
    {'osver': '16.04', 'pkgname': 'nginx', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '16.04', 'pkgname': 'nginx-common', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '16.04', 'pkgname': 'nginx-core', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '16.04', 'pkgname': 'nginx-extras', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '16.04', 'pkgname': 'nginx-full', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '16.04', 'pkgname': 'nginx-light', 'pkgver': '1.10.3-0ubuntu0.16.04.3'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-auth-pam', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-cache-purge', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-dav-ext', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-echo', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-fancyindex', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-geoip', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-headers-more-filter', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-image-filter', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-lua', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-ndk', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-perl', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-subs-filter', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-uploadprogress', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-upstream-fair', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-http-xslt-filter', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-mail', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-nchan', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-rtmp', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'libnginx-mod-stream', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx-common', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx-core', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx-extras', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx-full', 'pkgver': '1.14.0-0ubuntu1.2'},
    {'osver': '18.04', 'pkgname': 'nginx-light', 'pkgver': '1.14.0-0ubuntu1.2'}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var osver = NULL;
  var pkgname = NULL;
  var pkgver = NULL;
  if (!empty_or_null(package_array['osver'])) osver = package_array['osver'];
  if (!empty_or_null(package_array['pkgname'])) pkgname = package_array['pkgname'];
  if (!empty_or_null(package_array['pkgver'])) pkgver = package_array['pkgver'];
  if (osver && pkgname && pkgver) {
    if (ubuntu_check(osver:osver, pkgname:pkgname, pkgver:pkgver)) flag++;
  }
}

if (flag)
{
  var extra = '';
  extra += ubuntu_report_get();
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : extra
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'libnginx-mod-http-auth-pam / libnginx-mod-http-cache-purge / etc');
}