Libreswan 4.6 < 5.3.1 DoS

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

include('compat.inc');

if (description)
{
  script_id(327416);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/17");

  script_cve_id("CVE-2026-12413");
  script_xref(name:"IAVA", value:"2026-A-0685");

  script_name(english:"Libreswan 4.6 < 5.3.1 DoS");

  script_set_attribute(attribute:"synopsis", value:
"The version of Libreswan installed on the remote host is affected by a denial of service vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Libreswan installed on the remote host is between 4.6 and 5.3.1 (exclusive). It is, therefore, affected
by a denial of service vulnerability. An invalidly formatted IKEv2 fragment causes the Libreswan pluto daemon to crash
and restart. The function reassemble_v2_incoming_fragments() would ignore unknown outer payloads but still store these
in a fixed size array msg_digest.digest[PAYLIMIT]. An off-by-one error in the assertion causes the daemon to abort. No
remote code execution is possible. Any configuration that allows IKEv2 connections that do not set fragmentation=no are
vulnerable. IKEv1 is not affected.

Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.");
  script_set_attribute(attribute:"see_also", value:"https://libreswan.org/security/CVE-2026-12413/CVE-2026-12413.txt");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Libreswan version 5.3.1 or later.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-12413");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/06/24");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/06/24");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/16");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:libreswan:libreswan");
  script_set_attribute(attribute:"stig_severity", value:"I");
  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("libreswan_nix_installed.nbin");
  script_require_keys("installed_sw/Libreswan");

  exit(0);
}

include('vcf.inc');

var app = 'Libreswan';

var app_info = vcf::get_app_info(app:app);
vcf::check_all_backporting(app_info:app_info);

var constraints = [
  { 'min_version' : '4.6', 'fixed_version' : '5.3.1' }
];

vcf::check_version_and_report(
  app_info:app_info,
  constraints:constraints,
  severity:SECURITY_HOLE
);