Ubuntu 20.04 LTS / 22.04 LTS / 23.10 : Squid vulnerabilities (USN-6728-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-6728-1. The text
# itself is copyright (C) Canonical, Inc. See
# <https://ubuntu.com/security/notices>. Ubuntu(R) is a registered
# trademark of Canonical, Inc.
##

include('compat.inc');

if (description)
{
  script_id(193170);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/04/11");

  script_cve_id(
    "CVE-2023-5824",
    "CVE-2023-49288",
    "CVE-2024-23638",
    "CVE-2024-25111",
    "CVE-2024-25617"
  );
  script_xref(name:"USN", value:"6728-1");

  script_name(english:"Ubuntu 20.04 LTS / 22.04 LTS / 23.10 : Squid vulnerabilities (USN-6728-1)");

  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 20.04 LTS / 22.04 LTS / 23.10 host has packages installed that are affected by multiple
vulnerabilities as referenced in the USN-6728-1 advisory.

  - Squid is a caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Affected versions of squid are
    subject to a a Use-After-Free bug which can lead to a Denial of Service attack via collapsed forwarding.
    All versions of Squid from 3.5 up to and including 5.9 configured with collapsed_forwarding on are
    vulnerable. Configurations with collapsed_forwarding off or without a collapsed_forwarding directive
    are not vulnerable. This bug is fixed by Squid version 6.0.1. Users are advised to upgrade. Users unable
    to upgrade should remove all collapsed_forwarding lines from their squid.conf. (CVE-2023-49288)

  - Squid is vulnerable to Denial of Service attack against HTTP and HTTPS clients due to an Improper Handling
    of Structural Elements bug. (CVE-2023-5824)

  - Squid is a caching proxy for the Web. Due to an expired pointer reference bug, Squid prior to version 6.6
    is vulnerable to a Denial of Service attack against Cache Manager error responses. This problem allows a
    trusted client to perform Denial of Service when generating error pages for Client Manager reports. Squid
    older than 5.0.5 have not been tested and should be assumed to be vulnerable. All Squid-5.x up to and
    including 5.9 are vulnerable. All Squid-6.x up to and including 6.5 are vulnerable. This bug is fixed by
    Squid version 6.6. In addition, patches addressing this problem for the stable releases can be found in
    Squid's patch archives. As a workaround, prevent access to Cache Manager using Squid's main access
    control: `http_access deny manager`. (CVE-2024-23638)

  - Squid is a web proxy cache. Starting in version 3.5.27 and prior to version 6.8, Squid may be vulnerable
    to a Denial of Service attack against HTTP Chunked decoder due to an uncontrolled recursion bug. This
    problem allows a remote attacker to cause Denial of Service when sending a crafted, chunked, encoded HTTP
    Message. This bug is fixed in Squid version 6.8. In addition, patches addressing this problem for the
    stable releases can be found in Squid's patch archives. There is no workaround for this issue.
    (CVE-2024-25111)

  - Squid is an open source caching proxy for the Web supporting HTTP, HTTPS, FTP, and more. Due to a Collapse
    of Data into Unsafe Value bug ,Squid may be vulnerable to a Denial of Service attack against HTTP header
    parsing. This problem allows a remote client or a remote server to perform Denial of Service when sending
    oversized headers in HTTP messages. In versions of Squid prior to 6.5 this can be achieved if the
    request_header_max_size or reply_header_max_size settings are unchanged from the default. In Squid version
    6.5 and later, the default setting of these parameters is safe. Squid will emit a critical warning in
    cache.log if the administrator is setting these parameters to unsafe values. Squid will not at this time
    prevent these settings from being changed to unsafe values. Users are advised to upgrade to version 6.5.
    There are no known workarounds for this vulnerability. This issue is also tracked as SQUID-2024:2
    (CVE-2024-25617)

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-6728-1");
  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:C");
  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-2023-5824");

  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:"2023/11/03");
  script_set_attribute(attribute:"patch_publication_date", value:"2024/04/10");
  script_set_attribute(attribute:"plugin_publication_date", value:"2024/04/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:22.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:23.10");
  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-openssl");
  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: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) 2024 Canonical, Inc. / NASL script (C) 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 (! ('20.04' >< os_release || '22.04' >< os_release || '23.10' >< os_release)) audit(AUDIT_OS_NOT, 'Ubuntu 20.04 / 22.04 / 23.10', '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': '20.04', 'pkgname': 'squid', 'pkgver': '4.10-1ubuntu1.10'},
    {'osver': '20.04', 'pkgname': 'squid-cgi', 'pkgver': '4.10-1ubuntu1.10'},
    {'osver': '20.04', 'pkgname': 'squid-common', 'pkgver': '4.10-1ubuntu1.10'},
    {'osver': '20.04', 'pkgname': 'squid-purge', 'pkgver': '4.10-1ubuntu1.10'},
    {'osver': '20.04', 'pkgname': 'squidclient', 'pkgver': '4.10-1ubuntu1.10'},
    {'osver': '22.04', 'pkgname': 'squid', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '22.04', 'pkgname': 'squid-cgi', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '22.04', 'pkgname': 'squid-common', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '22.04', 'pkgname': 'squid-openssl', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '22.04', 'pkgname': 'squid-purge', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '22.04', 'pkgname': 'squidclient', 'pkgver': '5.7-0ubuntu0.22.04.4'},
    {'osver': '23.10', 'pkgname': 'squid', 'pkgver': '6.1-2ubuntu1.3'},
    {'osver': '23.10', 'pkgname': 'squid-cgi', 'pkgver': '6.1-2ubuntu1.3'},
    {'osver': '23.10', 'pkgname': 'squid-common', 'pkgver': '6.1-2ubuntu1.3'},
    {'osver': '23.10', 'pkgname': 'squid-openssl', 'pkgver': '6.1-2ubuntu1.3'},
    {'osver': '23.10', 'pkgname': 'squid-purge', 'pkgver': '6.1-2ubuntu1.3'},
    {'osver': '23.10', 'pkgname': 'squidclient', 'pkgver': '6.1-2ubuntu1.3'}
];

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-openssl / squid-purge / etc');
}