Linux Distros Unpatched Vulnerability : CVE-2026-29009

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

include('compat.inc');

if (description)
{
  script_id(325991);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/14");

  script_cve_id("CVE-2026-29009");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-29009");

  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.

  - U-Boot through 2026.04-rc3 contains a buffer overflow vulnerability in nfs_readlink_reply() (net/nfs-
    common.c) when CONFIG_CMD_NFS is enabled, allowing a malicious or compromised NFS server to overflow the
    2048-byte nfs_path_buff buffer by returning multiple relative symlink targets that are appended without
    cumulative length validation. Attackers can send two or more READLINK responses containing relative
    symlink targets of approximately 1100 bytes each to corrupt adjacent BSS variables including
    nfs_server_ip, nfs_server_mount_port, nfs_server_port, nfs_our_port, nfs_state, and rpc_id, potentially
    achieving memory corruption and control over the NFS client state machine. (CVE-2026-29009)

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-2026-29009");
  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:N/C:N/I:P/A:C");
  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:N/UI:N/S:U/C:N/I:L/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:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/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-2026-29009");

  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:"2026/07/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/09");

  script_set_attribute(attribute:"plugin_type", value:"local");
  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:canonical:ubuntu_linux:26.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:u-boot");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:u-boot-nezha");
  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-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", "Host/OS/Ubuntu Linux-26.04");

  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-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-amlogic"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-mvebu"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-qcom"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-amlogic"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-mvebu"},
          {"reference": "u-boot-nezha"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-qcom"},
          {"reference": "u-boot-qemu"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sifive"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-amlogic"},
          {"reference": "u-boot-asahi"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-microchip"},
          {"reference": "u-boot-mvebu"},
          {"reference": "u-boot-nezha"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-qcom"},
          {"reference": "u-boot-qemu"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sifive"},
          {"reference": "u-boot-starfive"},
          {"reference": "u-boot-stm32"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-amlogic"},
          {"reference": "u-boot-amlogic-binaries"},
          {"reference": "u-boot-asahi"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-exynos-binaries"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-microchip"},
          {"reference": "u-boot-mvebu"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-qcom"},
          {"reference": "u-boot-qemu"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sifive"},
          {"reference": "u-boot-sitara-binaries"},
          {"reference": "u-boot-starfive"},
          {"reference": "u-boot-stm32"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  },
  "Ubuntu Linux-26.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "26.04",
        "pkgs": [
          {"reference": "u-boot"},
          {"reference": "u-boot-amlogic"},
          {"reference": "u-boot-amlogic-binaries"},
          {"reference": "u-boot-asahi"},
          {"reference": "u-boot-exynos"},
          {"reference": "u-boot-exynos-binaries"},
          {"reference": "u-boot-imx"},
          {"reference": "u-boot-microchip"},
          {"reference": "u-boot-mvebu"},
          {"reference": "u-boot-omap"},
          {"reference": "u-boot-qcom"},
          {"reference": "u-boot-qemu"},
          {"reference": "u-boot-rockchip"},
          {"reference": "u-boot-rpi"},
          {"reference": "u-boot-sifive"},
          {"reference": "u-boot-sitara-binaries"},
          {"reference": "u-boot-starfive"},
          {"reference": "u-boot-stm32"},
          {"reference": "u-boot-sunxi"},
          {"reference": "u-boot-tegra"},
          {"reference": "u-boot-tools"}
        ]
      }
    ]
  }
};

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');
}