Ubuntu 16.04 LTS / 18.04 LTS : Squid vulnerabilities (USN-4213-1)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4213-1. 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(131723);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/20");

  script_cve_id(
    "CVE-2019-12523",
    "CVE-2019-12526",
    "CVE-2019-12854",
    "CVE-2019-18676",
    "CVE-2019-18677",
    "CVE-2019-18678",
    "CVE-2019-18679"
  );
  script_xref(name:"USN", value:"4213-1");

  script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS : Squid vulnerabilities (USN-4213-1)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Ubuntu host is missing one or more security updates.");
  script_set_attribute(attribute:"description", value:
"Jeriko One and Kristoffer Danielsson discovered that Squid incorrectly
handled certain URN requests. A remote attacker could possibly use
this issue to bypass access checks and access restricted servers. This
issue was only addressed in Ubuntu 19.04 and Ubuntu 19.10.
(CVE-2019-12523)

Jeriko One discovered that Squid incorrectly handed URN responses. A
remote attacker could use this issue to cause Squid to crash,
resulting in a denial of service, or possibly execute arbitrary code.
(CVE-2019-12526)

Alex Rousskov discovered that Squid incorrectly handled certain
strings. A remote attacker could possibly use this issue to cause
Squid to crash, resulting in a denial of service. This issue only
affected Ubuntu 19.04. (CVE-2019-12854)

Jeriko One and Kristoffer Danielsson discovered that Squid incorrectly
handled certain input. A remote attacker could use this issue to cause
Squid to crash, resulting in a denial of service, or possibly execute
arbitrary code. This issue was only addressed in Ubuntu 19.04 and
Ubuntu 19.10. (CVE-2019-18676)

Kristoffer Danielsson discovered that Squid incorrectly handled
certain messages. This issue could result in traffic being redirected
to origins it should not be delivered to. (CVE-2019-18677)

Regis Leroy discovered that Squid incorrectly handled certain HTTP
request headers. A remote attacker could use this to smuggle HTTP
requests and corrupt caches with arbitrary content. (CVE-2019-18678)

David Fifield discovered that Squid incorrectly handled HTTP Digest
Authentication. A remote attacker could possibly use this issue to
obtain pointer contents and bypass ASLR protections. (CVE-2019-18679).

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/notices/USN-4213-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  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: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-2019-12526");

  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:"2019/08/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/12/04");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/05");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squid");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squid-cgi");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squid-common");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squid-purge");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squid3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:squidclient");
  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:"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) 2019-2023 Canonical, Inc. / NASL script (C) 2019-2023 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 (! ('16.04' >< os_release || '18.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 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': '16.04', 'pkgname': 'squid', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '16.04', 'pkgname': 'squid-cgi', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '16.04', 'pkgname': 'squid-common', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '16.04', 'pkgname': 'squid-purge', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '16.04', 'pkgname': 'squid3', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '16.04', 'pkgname': 'squidclient', 'pkgver': '3.5.12-1ubuntu7.9'},
    {'osver': '18.04', 'pkgname': 'squid', 'pkgver': '3.5.27-1ubuntu1.4'},
    {'osver': '18.04', 'pkgname': 'squid-cgi', 'pkgver': '3.5.27-1ubuntu1.4'},
    {'osver': '18.04', 'pkgname': 'squid-common', 'pkgver': '3.5.27-1ubuntu1.4'},
    {'osver': '18.04', 'pkgname': 'squid-purge', 'pkgver': '3.5.27-1ubuntu1.4'},
    {'osver': '18.04', 'pkgname': 'squid3', 'pkgver': '3.5.27-1ubuntu1.4'},
    {'osver': '18.04', 'pkgname': 'squidclient', 'pkgver': '3.5.27-1ubuntu1.4'}
];

var flag = 0;
foreach 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)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  var tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'squid / squid-cgi / squid-common / squid-purge / squid3 / etc');
}