Linux Distros Unpatched Vulnerability : CVE-2026-75092

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

include('compat.inc');

if (description)
{
  script_id(345873);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/09/15");

  script_cve_id("CVE-2026-75092");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-75092");

  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 privilege escalation flaw was found in the scan_mysql actor of leapp-upgrade-el9toel10 (provided by
    leapp-repository). During RHEL 9 to RHEL 10 upgrades, the actor runs: mysqld --validate-config --log-
    error-verbosity=2 directly as root in the Leapp actor context, bypassing the packaged MySQL systemd unit
    that normally starts the daemon as User=mysql. A process compromised as the mysql OS identity can write a
    version-2 persisted configuration (mysqld-auto.cnf) and a malicious shared object into /var/lib/mysql (a
    directory owned by mysql). That persisted map can set plugin_dir to /var/lib/mysql and early_plugin_load
    (or related loader options such as plugin_load / plugin_load_add) so MySQL loads the attacker-controlled
    object during configuration validation. Plugin loading can reach dlopen() before MySQL's runtime-user
    check and before plugin-symbol validation. When an administrator subsequently runs the documented Leapp
    preupgrade or upgrade workflow, attacker-controlled code can execute as UID 0 with a full capability set
    in an unconfined SELinux domain (unconfined_t). The attack does not require write access to the default
    system plugin path under /usr; redirecting plugin_dir via mysql-owned persisted state is sufficient.
    Ordinary SQL privileges alone (including highly privileged SQL accounts) are not a sufficient startpoint 
    OS-level execution as the mysql service identity is required, plus later administrator invocation of
    Leapp. (CVE-2026-75092)

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-2026-75092");
  script_set_attribute(attribute:"solution", value:
"There is no known solution at this time.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_attribute(attribute:"risk_factor", value:"Medium");

  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:"2026/09/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/09/15");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:leapp-upgrade-el9toel10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:leapp-upgrade-el9toel10-deps");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:leapp-upgrade-el9toel10-fapolicyd");
  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/Red Hat Enterprise Linux-9");

  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/RedHat/rpm-list"))) audit(AUDIT_PACKAGE_LIST_MISSING);

include('linux_unpatched.inc');

var distro_constraints_array = {
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "leapp-upgrade-el9toel10"},
          {"reference": "leapp-upgrade-el9toel10-deps"},
          {"reference": "leapp-upgrade-el9toel10-fapolicyd"}
        ]
      }
    ]
  }
};

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 third_party_support = get_kb_item('Host/OS/extended-third-party');
if (!empty_or_null(third_party_support)) {
    var third_party_vendors = distro_constraints_values['third_party'];
    if (!empty_or_null(third_party_vendors)) {
        var vendor;
        foreach vendor (third_party_vendors) {
            if (vendor == third_party_support) exit(0, 'A third party management patch is available for this vulnerability from ' + vendor + '.\n');
        }
    }
}

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');
}