Linux Distros Unpatched Vulnerability : CVE-2026-40342

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

include('compat.inc');

if (description)
{
  script_id(307396);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/22");

  script_cve_id("CVE-2026-40342");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-40342");

  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.

  - Firebird is an open-source relational database management system. In versions prior to 5.0.4, 4.0.7 and
    3.0.14, the external engine plugin loader concatenates a user-supplied engine name into a filesystem path
    without filtering path separators or .. components. An authenticated user with CREATE FUNCTION privileges
    can use a crafted ENGINE name to load an arbitrary shared library from anywhere on the filesystem via path
    traversal. The library's initialization code executes immediately during loading, before Firebird
    validates the module, achieving code execution as the server's OS account. This issue has been fixed in
    versions 5.0.4, 4.0.7 and 3.0.14. (CVE-2026-40342)

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-2026-40342");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-40342");
  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:S/C:P/I:C/A:C");
  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:L/UI:N/S:C/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-40342");

  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:"2026/04/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/17");

  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:"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: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:"p-cpe:/a:canonical:ubuntu_linux:firebird3.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:firebird4.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:firebird3.0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:firebird4.0");
  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/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");

  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-11": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "11",
        "pkgs": [
          {"reference": "firebird-dev"},
          {"reference": "firebird3.0-common"},
          {"reference": "firebird3.0-common-doc"},
          {"reference": "firebird3.0-doc"},
          {"reference": "firebird3.0-examples"},
          {"reference": "firebird3.0-server"},
          {"reference": "firebird3.0-server-core"},
          {"reference": "firebird3.0-utils"},
          {"reference": "libfbclient2"},
          {"reference": "libib-util"}
        ]
      }
    ]
  },
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "firebird-dev"},
          {"reference": "firebird3.0-common"},
          {"reference": "firebird3.0-common-doc"},
          {"reference": "firebird3.0-doc"},
          {"reference": "firebird3.0-examples"},
          {"reference": "firebird3.0-server"},
          {"reference": "firebird3.0-server-core"},
          {"reference": "firebird3.0-utils"},
          {"reference": "libfbclient2"},
          {"reference": "libib-util"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "firebird-dev"},
          {"reference": "firebird-utils"},
          {"reference": "firebird3.0-common"},
          {"reference": "firebird3.0-common-doc"},
          {"reference": "firebird3.0-doc"},
          {"reference": "firebird3.0-examples"},
          {"reference": "firebird3.0-server"},
          {"reference": "firebird3.0-server-core"},
          {"reference": "firebird3.0-utils"},
          {"reference": "firebird4.0-common"},
          {"reference": "firebird4.0-common-doc"},
          {"reference": "firebird4.0-doc"},
          {"reference": "firebird4.0-examples"},
          {"reference": "firebird4.0-server"},
          {"reference": "firebird4.0-server-core"},
          {"reference": "firebird4.0-utils"},
          {"reference": "libfbclient2"},
          {"reference": "libib-util"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "firebird3.0"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "firebird3.0"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "firebird3.0"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "firebird3.0"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "firebird3.0"},
          {"reference": "firebird4.0"}
        ]
      }
    ]
  }
};

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_HOLE,
      extra      : report
  );
  exit(0);
}
else
{
  audit(AUDIT_HOST_NOT, 'affected');
}