Linux Distros Unpatched Vulnerability : CVE-2021-32842

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
##

include('compat.inc');

if (description)
{
  script_id(259398);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/21");

  script_cve_id("CVE-2021-32842");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2021-32842");

  script_set_attribute(attribute:"synopsis", value:
"The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be
patched.");
  script_set_attribute(attribute:"description", value:
"The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied
patch available.

  - SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Starting version 1.0.0 and prior to
    version 1.3.3, a check was added if the destination file is under a destination directory. However, it is
    not enforced that `_baseDirectory` ends with slash. If the _baseDirectory is not slash terminated like
    `/home/user/dir` it is possible to create a file with a name thats begins as the destination directory one
    level up from the directory, i.e. `/home/user/dir.sh`. Because of the file name and destination directory
    constraints, the arbitrary file creation impact is limited and depends on the use case. Version 1.3.3
    fixed this vulnerability. (CVE-2021-32842)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2021-32842");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-32842");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2022/01/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2025/08/30");

  script_set_attribute(attribute:"plugin_type", value:"local");
  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:"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:24.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:25.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:25.10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:mono");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Misc.");

  script_copyright(english:"This script is Copyright (C) 2025-2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info2.nasl", "set_linux_os_id.nasl");
  script_require_keys("Host/cpu", "Host/local_checks_enabled", "global_settings/vendor_unpatched", "Host/OS/identifier");
  script_require_ports("Host/OS/Ubuntu Linux-14.04", "Host/OS/Ubuntu Linux-16.04", "Host/OS/Ubuntu Linux-18.04", "Host/OS/Ubuntu Linux-20.04", "Host/OS/Ubuntu Linux-22.04", "Host/OS/Ubuntu Linux-24.04", "Host/OS/Ubuntu Linux-25.04", "Host/OS/Ubuntu Linux-25.10");

  exit(0);
}

if (!get_kb_item("global_settings/vendor_unpatched")) exit(0, "Unpatched Vulnerabilities Detection not active.");
if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (empty_or_null(get_one_kb_item("Host/Debian/dpkg-l"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "libmono-2.0-1"},
          {"reference": "libmono-2.0-dev"},
          {"reference": "libmono-c5-1.1-cil"},
          {"reference": "libmono-cecil-private-cil"},
          {"reference": "libmono-cil-dev"},
          {"reference": "libmono-codecontracts4.0-cil"},
          {"reference": "libmono-compilerservices-symbolwriter4.0-cil"},
          {"reference": "libmono-csharp4.0c-cil"},
          {"reference": "libmono-entityframework-sqlserver6.0-cil"},
          {"reference": "libmono-entityframework6.0-cil"},
          {"reference": "libmono-http4.0-cil"},
          {"reference": "libmono-management2.0-cil"},
          {"reference": "libmono-management4.0-cil"},
          {"reference": "libmono-messaging-rabbitmq2.0-cil"},
          {"reference": "libmono-messaging-rabbitmq4.0-cil"},
          {"reference": "libmono-messaging2.0-cil"},
          {"reference": "libmono-messaging4.0-cil"},
          {"reference": "libmono-opensystem-c4.0-cil"},
          {"reference": "libmono-posix2.0-cil"},
          {"reference": "libmono-posix4.0-cil"},
          {"reference": "libmono-profiler"},
          {"reference": "libmono-rabbitmq2.0-cil"},
          {"reference": "libmono-rabbitmq4.0-cil"},
          {"reference": "libmono-simd2.0-cil"},
          {"reference": "libmono-web4.0-cil"},
          {"reference": "libmono-webbrowser2.0-cil"},
          {"reference": "libmono-webbrowser4.0-cil"},
          {"reference": "libmono2.0-cil"},
          {"reference": "libmonoboehm-2.0-1"},
          {"reference": "libmonoboehm-2.0-1-dbg"},
          {"reference": "libmonoboehm-2.0-dev"},
          {"reference": "libmonosgen-2.0-1"},
          {"reference": "libmonosgen-2.0-1-dbg"},
          {"reference": "libmonosgen-2.0-dev"},
          {"reference": "mono-complete"},
          {"reference": "mono-runtime"},
          {"reference": "mono-runtime-boehm"},
          {"reference": "mono-runtime-common"},
          {"reference": "mono-runtime-dbg"},
          {"reference": "mono-runtime-sgen"},
          {"reference": "mono-utils"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "ca-certificates-mono"},
          {"reference": "libmono-2.0-1"},
          {"reference": "libmono-2.0-dev"},
          {"reference": "libmono-c5-1.1-cil"},
          {"reference": "libmono-cecil-private-cil"},
          {"reference": "libmono-cil-dev"},
          {"reference": "libmono-codecontracts4.0-cil"},
          {"reference": "libmono-compilerservices-symbolwriter4.0-cil"},
          {"reference": "libmono-corlib4.5-cil"},
          {"reference": "libmono-csharp4.0c-cil"},
          {"reference": "libmono-http4.0-cil"},
          {"reference": "libmono-i18n-cjk4.0-cil"},
          {"reference": "libmono-i18n-mideast4.0-cil"},
          {"reference": "libmono-i18n-other4.0-cil"},
          {"reference": "libmono-i18n-rare4.0-cil"},
          {"reference": "libmono-i18n-west4.0-cil"},
          {"reference": "libmono-i18n4.0-all"},
          {"reference": "libmono-i18n4.0-cil"},
          {"reference": "libmono-management4.0-cil"},
          {"reference": "libmono-messaging-rabbitmq4.0-cil"},
          {"reference": "libmono-messaging4.0-cil"},
          {"reference": "libmono-parallel4.0-cil"},
          {"reference": "libmono-posix4.0-cil"},
          {"reference": "libmono-profiler"},
          {"reference": "libmono-rabbitmq4.0-cil"},
          {"reference": "libmono-simd4.0-cil"},
          {"reference": "libmono-smdiagnostics0.0-cil"},
          {"reference": "libmono-system4.0-cil"},
          {"reference": "libmono-webbrowser4.0-cil"},
          {"reference": "libmonoboehm-2.0-1"},
          {"reference": "libmonoboehm-2.0-1-dbg"},
          {"reference": "libmonoboehm-2.0-dev"},
          {"reference": "libmonosgen-2.0-1"},
          {"reference": "libmonosgen-2.0-1-dbg"},
          {"reference": "libmonosgen-2.0-dev"},
          {"reference": "mono-complete"},
          {"reference": "mono-runtime"},
          {"reference": "mono-runtime-boehm"},
          {"reference": "mono-runtime-common"},
          {"reference": "mono-runtime-dbg"},
          {"reference": "mono-runtime-sgen"},
          {"reference": "mono-utils"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.04",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "mono"}
        ]
      }
    ]
  }
};

var distro_constraints_values = linux_unpatched::get_distro_constraints(distro_constraints_arr:distro_constraints_array);
if (empty_or_null(distro_constraints_values)) audit(AUDIT_HOST_NOT, 'affected');
var report = linux_unpatched::check_unpatched_constraints(distro_constraints_values:distro_constraints_values);

if (!empty_or_null(report))
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}