Linux Distros Unpatched Vulnerability : CVE-2026-26157

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

include('compat.inc');

if (description)
{
  script_id(298800);
  script_version("1.8");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/22");

  script_cve_id("CVE-2026-26157");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-26157");

  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 flaw was found in BusyBox. Incomplete path sanitization in its archive extraction utilities allows an
    attacker to craft malicious archives that when extracted, and under specific conditions, may write to
    files outside the intended directory. This can lead to arbitrary file overwrite, potentially enabling code
    execution through the modification of sensitive system files. (CVE-2026-26157)

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-2026-26157");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-26157");
  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:L/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:N/UI:R/S:U/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-2026-26157");

  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:"2026/02/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/02/12");

  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: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:busybox");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:busybox");
  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-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");

  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": "busybox"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Debian Linux-12": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "12",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Debian Linux-13": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "13",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "busybox"},
          {"reference": "busybox-initramfs"},
          {"reference": "busybox-static"},
          {"reference": "busybox-syslogd"},
          {"reference": "busybox-udeb"},
          {"reference": "udhcpc"},
          {"reference": "udhcpd"}
        ]
      }
    ]
  }
};

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');
}