Linux Distros Unpatched Vulnerability : CVE-2026-21968

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

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  script_id(297725);
  script_version("1.14");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/14");

  script_cve_id("CVE-2026-21968");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-21968");

  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.

  - Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported
    versions that are affected are 8.0.0-8.0.44, 8.4.0-8.4.7 and 9.0.0-9.5.0. Easily exploitable vulnerability
    allows low privileged attacker with network access via multiple protocols to compromise MySQL Server.
    Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently
    repeatable crash (complete DOS) of MySQL Server. (CVE-2026-21968)

Note that Nessus relies on the presence of the package as reported by the vendor.");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/cve-2026-21968");
  script_set_attribute(attribute:"see_also", value:"https://security-tracker.debian.org/tracker/CVE-2026-21968");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-21968");
  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: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:L/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-2026-21968");

  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:"2026/01/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/02/03");

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  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04:-:lts");
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  exit(0);
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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")) && empty_or_null(get_one_kb_item("Host/RedHat/rpm-list"))) 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": "libmariadb-dev"},
          {"reference": "libmariadb-dev-compat"},
          {"reference": "libmariadb3"},
          {"reference": "libmariadbd-dev"},
          {"reference": "libmariadbd19"},
          {"reference": "mariadb-backup"},
          {"reference": "mariadb-client"},
          {"reference": "mariadb-client-core"},
          {"reference": "mariadb-common"},
          {"reference": "mariadb-plugin-connect"},
          {"reference": "mariadb-plugin-cracklib-password-check"},
          {"reference": "mariadb-plugin-gssapi-client"},
          {"reference": "mariadb-plugin-gssapi-server"},
          {"reference": "mariadb-plugin-hashicorp-key-management"},
          {"reference": "mariadb-plugin-mroonga"},
          {"reference": "mariadb-plugin-oqgraph"},
          {"reference": "mariadb-plugin-provider-bzip2"},
          {"reference": "mariadb-plugin-provider-lz4"},
          {"reference": "mariadb-plugin-provider-lzma"},
          {"reference": "mariadb-plugin-provider-lzo"},
          {"reference": "mariadb-plugin-provider-snappy"},
          {"reference": "mariadb-plugin-rocksdb"},
          {"reference": "mariadb-plugin-s3"},
          {"reference": "mariadb-plugin-spider"},
          {"reference": "mariadb-server"},
          {"reference": "mariadb-server-10.5"},
          {"reference": "mariadb-server-core"},
          {"reference": "mariadb-test"},
          {"reference": "mariadb-test-data"}
        ]
      }
    ]
  },
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "libmysqlclient-dev"},
          {"reference": "libmysqlclient18"},
          {"reference": "libmysqld-dev"},
          {"reference": "libmysqld-pic"},
          {"reference": "mysql-client"},
          {"reference": "mysql-client-5.5"},
          {"reference": "mysql-client-core-5.5"},
          {"reference": "mysql-common"},
          {"reference": "mysql-server"},
          {"reference": "mysql-server-5.5"},
          {"reference": "mysql-server-core-5.5"},
          {"reference": "mysql-source-5.5"},
          {"reference": "mysql-testsuite"},
          {"reference": "mysql-testsuite-5.5"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "libmysqlclient-dev"},
          {"reference": "libmysqlclient20"},
          {"reference": "libmysqld-dev"},
          {"reference": "mariadb-10.0"},
          {"reference": "mysql-client"},
          {"reference": "mysql-client-5.7"},
          {"reference": "mysql-client-core-5.7"},
          {"reference": "mysql-common"},
          {"reference": "mysql-server"},
          {"reference": "mysql-server-5.7"},
          {"reference": "mysql-server-core-5.7"},
          {"reference": "mysql-source-5.7"},
          {"reference": "mysql-testsuite"},
          {"reference": "mysql-testsuite-5.7"},
          {"reference": "percona-server-5.6"},
          {"reference": "percona-xtradb-cluster-5.6"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "libmysqlclient-dev"},
          {"reference": "libmysqlclient20"},
          {"reference": "libmysqld-dev"},
          {"reference": "mariadb-10.1"},
          {"reference": "mysql-client"},
          {"reference": "mysql-client-5.7"},
          {"reference": "mysql-client-core-5.7"},
          {"reference": "mysql-server"},
          {"reference": "mysql-server-5.7"},
          {"reference": "mysql-server-core-5.7"},
          {"reference": "mysql-source-5.7"},
          {"reference": "mysql-testsuite"},
          {"reference": "mysql-testsuite-5.7"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "mariadb-10.3"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "mariadb-10.6"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "mariadb"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "mariadb"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "mariadb"},
          {"reference": "mariadb-backup"},
          {"reference": "mariadb-client-utils"},
          {"reference": "mariadb-common"},
          {"reference": "mariadb-devel"},
          {"reference": "mariadb-embedded"},
          {"reference": "mariadb-embedded-devel"},
          {"reference": "mariadb-errmsg"},
          {"reference": "mariadb-gssapi-server"},
          {"reference": "mariadb-oqgraph-engine"},
          {"reference": "mariadb-pam"},
          {"reference": "mariadb-server"},
          {"reference": "mariadb-server-galera"},
          {"reference": "mariadb-server-utils"},
          {"reference": "mariadb-test"},
          {"reference": "mariadb10.11"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "mariadb"},
          {"reference": "mariadb-backup"},
          {"reference": "mariadb-common"},
          {"reference": "mariadb-devel"},
          {"reference": "mariadb-embedded"},
          {"reference": "mariadb-embedded-devel"},
          {"reference": "mariadb-errmsg"},
          {"reference": "mariadb-gssapi-server"},
          {"reference": "mariadb-oqgraph-engine"},
          {"reference": "mariadb-pam"},
          {"reference": "mariadb-server"},
          {"reference": "mariadb-server-galera"},
          {"reference": "mariadb-server-utils"},
          {"reference": "mariadb-test"}
        ]
      }
    ]
  }
};

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');
}