Ubuntu 18.04 LTS / 20.04 LTS : Squid vulnerabilities (USN-4981-1)

#%NASL_MIN_LEVEL 70300
##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4981-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

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

if (description)
{
  script_id(150232);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/08/27");

  script_cve_id(
    "CVE-2021-28651",
    "CVE-2021-28652",
    "CVE-2021-28662",
    "CVE-2021-31806",
    "CVE-2021-31807",
    "CVE-2021-31808",
    "CVE-2021-33620"
  );
  script_xref(name:"USN", value:"4981-1");

  script_name(english:"Ubuntu 18.04 LTS / 20.04 LTS : Squid vulnerabilities (USN-4981-1)");

  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 18.04 LTS / 20.04 LTS host has packages installed that are affected by multiple vulnerabilities as
referenced in the USN-4981-1 advisory.

    Joshua Rogers discovered that Squid incorrectly handled requests with the urn: scheme. A remote attacker
    could possibly use this issue to cause Squid to consume resources, leading to a denial of service.
    (CVE-2021-28651)

    Joshua Rogers discovered that Squid incorrectly handled requests to the Cache Manager API. A remote
    attacker with access privileges could possibly use this issue to cause Squid to consume resources, leading
    to a denial of service. This issue was only addressed in Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04.
    (CVE-2021-28652)

    Joshua Rogers discovered that Squid incorrectly handled certain response headers. A remote attacker could
    possibly use this issue to cause Squid to crash, resulting in a denial of service. This issue was only
    affected Ubuntu 20.04 LTS, Ubuntu 20.10, and Ubuntu 21.04. (CVE-2021-28662)

    Joshua Rogers discovered that Squid incorrectly handled range request processing. A remote attacker could
    possibly use this issue to cause Squid to crash, resulting in a denial of service. (CVE-2021-31806,
    CVE-2021-31807, CVE-2021-31808)

    Joshua Rogers discovered that Squid incorrectly handled certain HTTP responses. A remote attacker could
    possibly use this issue to cause Squid to crash, resulting in a denial of service. (CVE-2021-33620)

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-4981-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/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:N/I:N/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-2021-28651");

  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:"2021/06/03");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/06/03");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  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:"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) 2021-2024 Canonical, Inc. / NASL script (C) 2021-2024 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 (! ('18.04' >< os_release || '20.04' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 18.04 / 20.04', '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': '18.04', 'pkgname': 'squid', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '18.04', 'pkgname': 'squid-cgi', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '18.04', 'pkgname': 'squid-common', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '18.04', 'pkgname': 'squid-purge', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '18.04', 'pkgname': 'squid3', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '18.04', 'pkgname': 'squidclient', 'pkgver': '3.5.27-1ubuntu1.11'},
    {'osver': '20.04', 'pkgname': 'squid', 'pkgver': '4.10-1ubuntu1.4'},
    {'osver': '20.04', 'pkgname': 'squid-cgi', 'pkgver': '4.10-1ubuntu1.4'},
    {'osver': '20.04', 'pkgname': 'squid-common', 'pkgver': '4.10-1ubuntu1.4'},
    {'osver': '20.04', 'pkgname': 'squid-purge', 'pkgver': '4.10-1ubuntu1.4'},
    {'osver': '20.04', 'pkgname': 'squidclient', 'pkgver': '4.10-1ubuntu1.4'}
];

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, 'squid / squid-cgi / squid-common / squid-purge / squid3 / etc');
}