Ubuntu 16.04 ESM : containerd vulnerabilities (USN-5521-1)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-5521-1. 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(183540);
  script_version("1.0");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/10/20");

  script_cve_id(
    "CVE-2021-32760",
    "CVE-2021-41103",
    "CVE-2022-23648",
    "CVE-2022-31030"
  );
  script_xref(name:"USN", value:"5521-1");

  script_name(english:"Ubuntu 16.04 ESM : containerd vulnerabilities (USN-5521-1)");

  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 16.04 ESM host has a package installed that is affected by multiple vulnerabilities as referenced in
the USN-5521-1 advisory.

  - containerd is a container runtime. A bug was found in containerd versions prior to 1.4.8 and 1.5.4 where
    pulling and extracting a specially-crafted container image can result in Unix file permission changes for
    existing files in the host's filesystem. Changes to file permissions can deny access to the expected owner
    of the file, widen access to others, or set extended bits like setuid, setgid, and sticky. This bug does
    not directly allow files to be read, modified, or executed without an additional cooperating process. This
    bug has been fixed in containerd 1.5.4 and 1.4.8. As a workaround, ensure that users only pull images from
    trusted sources. Linux security modules (LSMs) like SELinux and AppArmor can limit the files potentially
    affected by this bug through policies and profiles that prevent containerd from interacting with specific
    files. (CVE-2021-32760)

  - containerd is an open source container runtime with an emphasis on simplicity, robustness and portability.
    A bug was found in containerd where container root directories and some plugins had insufficiently
    restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and
    execute programs. When containers included executable programs with extended permission bits (such as
    setuid), unprivileged Linux users could discover and execute those programs. When the UID of an
    unprivileged Linux user on the host collided with the file owner or group inside a container, the
    unprivileged Linux user on the host could discover, read, and modify those files. This vulnerability has
    been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are
    released and may restart containers or update directory permissions to mitigate the vulnerability. Users
    unable to update should limit access to the host to trusted users. Update directory permission on
    container bundles directories. (CVE-2021-41103)

  - containerd is a container runtime available as a daemon for Linux and Windows. A bug was found in
    containerd prior to versions 1.6.1, 1.5.10, and 1.14.12 where containers launched through containerd's CRI
    implementation on Linux with a specially-crafted image configuration could gain access to read-only copies
    of arbitrary files and directories on the host. This may bypass any policy-based enforcement on container
    setup (including a Kubernetes Pod Security Policy) and expose potentially sensitive information.
    Kubernetes and crictl can both be configured to use containerd's CRI implementation. This bug has been
    fixed in containerd 1.6.1, 1.5.10, and 1.4.12. Users should update to these versions to resolve the issue.
    (CVE-2022-23648)

  - containerd is an open source container runtime. A bug was found in the containerd's CRI implementation
    where programs inside a container can cause the containerd daemon to consume memory without bound during
    invocation of the `ExecSync` API. This can cause containerd to consume all available memory on the
    computer, denying service to other legitimate workloads. Kubernetes and crictl can both be configured to
    use containerd's CRI implementation; `ExecSync` may be used when running probes or when executing
    processes via an exec facility. This bug has been fixed in containerd 1.6.6 and 1.5.13. Users should
    update to these versions to resolve the issue. Users unable to upgrade should ensure that only trusted
    images and commands are used. (CVE-2022-31030)

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-5521-1");
  script_set_attribute(attribute:"solution", value:
"Update the affected containerd package.");
  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-2021-41103");

  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:"2021/07/19");
  script_set_attribute(attribute:"patch_publication_date", value:"2022/07/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/10/20");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04:-:esm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:containerd");
  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) 2023 Canonical, Inc. / NASL script (C) 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)) audit(AUDIT_OS_NOT, 'Ubuntu 16.04', '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': 'containerd', 'pkgver': '1.2.6-0ubuntu1~16.04.6+esm2'}
];

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, 'containerd');
}