Linux Distros Unpatched Vulnerability : CVE-2026-21713

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

include('compat.inc');

if (description)
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  script_id(303615);
  script_version("1.12");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/05/25");

  script_cve_id("CVE-2026-21713");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-21713");

  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 in Node.js HMAC verification uses a non-constant-time comparison when validating user-provided
    signatures, potentially leaking timing information proportional to the number of matching bytes. Under
    certain threat models where high-resolution timing measurements are possible, this behavior could be
    exploited as a timing oracle to infer HMAC values. Node.js already provides timing-safe comparison
    primitives used elsewhere in the codebase, indicating this is an oversight rather than an intentional
    design decision. This vulnerability affects **20.x, 22.x, 24.x, and 25.x**. (CVE-2026-21713)

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-2026-21713");
  script_set_attribute(attribute:"see_also", value:"https://ubuntu.com/security/CVE-2026-21713");
  script_set_attribute(attribute:"solution", value:
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  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:U/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-21713");

  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:"2026/03/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/03/25");

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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/CentOS/rpm-list")) && 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 = {
  "Ubuntu Linux-14.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "14.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-16.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "16.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-18.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "18.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-20.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "20.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-22.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "22.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-24.04": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "24.04",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Ubuntu Linux-25.10": {
    "package_manager": "dpkg-l",
    "constraints": [
      {
        "release": "25.10",
        "pkgs": [
          {"reference": "nodejs"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "nodejs"},
          {"reference": "nodejs-devel"},
          {"reference": "nodejs-docs"},
          {"reference": "nodejs-full-i18n"},
          {"reference": "nodejs-libs"},
          {"reference": "nodejs-npm"},
          {"reference": "nodejs22"}
        ]
      }
    ]
  },
  "CentOS Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "nodejs"},
          {"reference": "nodejs-devel"},
          {"reference": "nodejs-docs"},
          {"reference": "nodejs-full-i18n"},
          {"reference": "nodejs-libs"},
          {"reference": "nodejs-nodemon"},
          {"reference": "nodejs-packaging"},
          {"reference": "nodejs-packaging-bundler"},
          {"reference": "npm"},
          {"reference": "v8-12.4-devel"},
          {"reference": "v8-13.6-devel"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "nodejs"},
          {"reference": "nodejs-devel"},
          {"reference": "nodejs-docs"},
          {"reference": "nodejs-full-i18n"},
          {"reference": "nodejs-libs"},
          {"reference": "nodejs-nodemon"},
          {"reference": "nodejs-packaging"},
          {"reference": "nodejs-packaging-bundler"},
          {"reference": "npm"},
          {"reference": "v8-12.4-devel"},
          {"reference": "v8-13.6-devel"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "nodejs"},
          {"reference": "nodejs-docs"},
          {"reference": "nodejs-full-i18n"},
          {"reference": "nodejs-libs"},
          {"reference": "npm"}
        ]
      }
    ]
  }
};

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');
}