Linux Distros Unpatched Vulnerability : CVE-2026-15812

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

include('compat.inc');

if (description)
{
  script_id(328673);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/22");

  script_cve_id("CVE-2026-15812");

  script_name(english:"Linux Distros Unpatched Vulnerability : CVE-2026-15812");

  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 vulnerability was found in the internal Access Control List (ACL) subsystem of kronosnet (Version
    affected: <= 1.34). When the framework is explicitly configured to manage dynamic links (accepting network
    traffic from any IP address) without network payload encryption, the validation architecture implicitly
    trusts the link ID provided within incoming data packets. A remote, unauthenticated attacker can exploit
    this lack of validation by spoofing a legitimate link ID inside crafted network frames. This allows the
    attacker to fully bypass the ACL framework and inject arbitrary data packets into the application layer,
    potentially leading to data corruption or service instabilities. (CVE-2026-15812)

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-2026-15812");
  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:H/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:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:U/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-15812");

  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:"2026/07/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:centos:centos:8");
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  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:9");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:centos:centos:libknet1");
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  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/CentOS Linux-8", "Host/OS/Red Hat Enterprise Linux-10", "Host/OS/Red Hat Enterprise Linux-8", "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/CentOS/rpm-list")) && 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-10": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "10",
        "pkgs": [
          {"reference": "libknet1"},
          {"reference": "libknet1-compress-bzip2-plugin"},
          {"reference": "libknet1-compress-lz4-plugin"},
          {"reference": "libknet1-compress-lzma-plugin"},
          {"reference": "libknet1-compress-lzo2-plugin"},
          {"reference": "libknet1-compress-plugins-all"},
          {"reference": "libknet1-compress-zlib-plugin"},
          {"reference": "libknet1-compress-zstd-plugin"},
          {"reference": "libknet1-crypto-nss-plugin"},
          {"reference": "libknet1-crypto-openssl-plugin"},
          {"reference": "libknet1-crypto-plugins-all"},
          {"reference": "libknet1-devel"},
          {"reference": "libknet1-plugins-all"},
          {"reference": "libnozzle1"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-9": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "9",
        "pkgs": [
          {"reference": "libknet1"},
          {"reference": "libknet1-compress-bzip2-plugin"},
          {"reference": "libknet1-compress-lz4-plugin"},
          {"reference": "libknet1-compress-lzma-plugin"},
          {"reference": "libknet1-compress-lzo2-plugin"},
          {"reference": "libknet1-compress-plugins-all"},
          {"reference": "libknet1-compress-zlib-plugin"},
          {"reference": "libknet1-compress-zstd-plugin"},
          {"reference": "libknet1-crypto-nss-plugin"},
          {"reference": "libknet1-crypto-openssl-plugin"},
          {"reference": "libknet1-crypto-plugins-all"},
          {"reference": "libknet1-devel"},
          {"reference": "libknet1-plugins-all"},
          {"reference": "libnozzle1"}
        ]
      }
    ]
  },
  "CentOS Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "libknet1"},
          {"reference": "libknet1-compress-bzip2-plugin"},
          {"reference": "libknet1-compress-lz4-plugin"},
          {"reference": "libknet1-compress-lzma-plugin"},
          {"reference": "libknet1-compress-lzo2-plugin"},
          {"reference": "libknet1-compress-plugins-all"},
          {"reference": "libknet1-compress-zlib-plugin"},
          {"reference": "libknet1-crypto-nss-plugin"},
          {"reference": "libknet1-crypto-openssl-plugin"},
          {"reference": "libknet1-crypto-plugins-all"},
          {"reference": "libknet1-devel"},
          {"reference": "libknet1-plugins-all"},
          {"reference": "libnozzle1"}
        ]
      }
    ]
  },
  "Red Hat Enterprise Linux-8": {
    "package_manager": "rpm-list",
    "constraints": [
      {
        "release": "8",
        "pkgs": [
          {"reference": "libknet1"},
          {"reference": "libknet1-compress-bzip2-plugin"},
          {"reference": "libknet1-compress-lz4-plugin"},
          {"reference": "libknet1-compress-lzma-plugin"},
          {"reference": "libknet1-compress-lzo2-plugin"},
          {"reference": "libknet1-compress-plugins-all"},
          {"reference": "libknet1-compress-zlib-plugin"},
          {"reference": "libknet1-crypto-nss-plugin"},
          {"reference": "libknet1-crypto-openssl-plugin"},
          {"reference": "libknet1-crypto-plugins-all"},
          {"reference": "libknet1-devel"},
          {"reference": "libknet1-plugins-all"},
          {"reference": "libnozzle1"}
        ]
      }
    ]
  }
};

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');
}