Linux Distros Unpatched Vulnerability : CVE-2026-20244

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

include('compat.inc');

if (description)
{
  script_id(324764);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/02");

  script_cve_id("CVE-2026-20244");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-20244");

  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.

  - A vulnerability in the DMG file format parser of ClamAV could allow an unauthenticated, remote attacker to
    cause a DoS condition, or possibly other expanded impacts, resulting from memory corruption on an affected
    device. This vulnerability is due to improper boundary checks for content in DMG files during scanning,
    which may result in an integer overflow on 32-bit platforms only. An attacker could exploit this
    vulnerability by submitting a crafted file that contains DMG content to be scanned by ClamAV on an
    affected device. A successful exploit could allow the attacker to cause the ClamAV scanning process to
    terminate, resulting in a DoS condition on the affected software. (CVE-2026-20244)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-20244");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-20244");
  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:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/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:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-20244");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_set_attribute(attribute:"vendor_unpatched", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/07/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/02");

  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:25.10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:11.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:12.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:13.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:14.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:clamav");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:clamav");
  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) 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/Debian Linux-11", "Host/OS/Debian Linux-12", "Host/OS/Debian Linux-13", "Host/OS/Debian Linux-14", "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-25.10", "Host/OS/Ubuntu Linux-26.04");

  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 = {
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-doc"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav12"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-doc"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav12"}
        ]
      }
    ]
  },
  "Debian Linux-14": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-doc"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav12"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-doc"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav12"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-doc"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav12"}
        ]
      }
    ]
  },
  "Debian Linux-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav9"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav9"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav9"}
        ]
      }
    ]
  },
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-dbg"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav6"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-dbg"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav7"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav7"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "clamav"},
          {"reference": "clamav-base"},
          {"reference": "clamav-daemon"},
          {"reference": "clamav-docs"},
          {"reference": "clamav-freshclam"},
          {"reference": "clamav-milter"},
          {"reference": "clamav-testfiles"},
          {"reference": "clamdscan"},
          {"reference": "libclamav-dev"},
          {"reference": "libclamav11t64"}
        ]
      }
    ]
  }
};

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');
}