Linux Distros Unpatched Vulnerability : CVE-2026-86692

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

include('compat.inc');

if (description)
{
  script_id(379096);
  script_version("1.1");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/11/11");

  script_cve_id("CVE-2026-86692");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-86692");

  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.

  - In apport before 2.37.0, a path traversal vulnerability allows an attacker who can supply a crafted crash
    report to cause unintended file creation or overwrite outside the intended extraction directory when the
    report is processed with apport-unpack. The key-name validation added for CVE-2026-77113 does not cover
    base64-encoded keys skipped by ProblemReport.load(binary=False), and ProblemReport.extract_keys() writes
    them to a file path built from the key without validation. This allows an attacker to create or overwrite
    arbitrary files writable by the invoking user, such as .bashrc or .profile, gaining persistence or code
    execution in that user's context. (CVE-2026-86692)

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-2026-86692");
  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:M/Au:N/C:N/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N");
  script_set_attribute(attribute:"cvss4_threat_vector", value:"CVSS:4.0/E:U");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-86692");

  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:"2026/11/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/11/11");

  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:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:26.10");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:apport");
  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/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-26.04", "Host/OS/Ubuntu Linux-26.10");

  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": "apport"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python-apport"},
          {"reference": "python-problem-report"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python-apport"},
          {"reference": "python-problem-report"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python-apport"},
          {"reference": "python-problem-report"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-core-dump-handler"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-core-dump-handler"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.10",
        "pkgs": [
          {"reference": "apport"},
          {"reference": "apport-core-dump-handler"},
          {"reference": "apport-gtk"},
          {"reference": "apport-kde"},
          {"reference": "apport-noui"},
          {"reference": "apport-retrace"},
          {"reference": "apport-valgrind"},
          {"reference": "dh-apport"},
          {"reference": "python3-apport"},
          {"reference": "python3-problem-report"}
        ]
      }
    ]
  }
};

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');
}