7-Zip < 26.01 NTFS Heap Buffer Overflow (GHSL-2026-140)

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

include('compat.inc');

if (description)
{
  script_id(327608);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/07/20");

  script_cve_id("CVE-2026-48095");

  script_name(english:"7-Zip < 26.01 NTFS Heap Buffer Overflow (GHSL-2026-140)");

  script_set_attribute(attribute:"synopsis", value:
"The remote host has an application installed that is affected by a heap buffer overflow vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of 7-Zip installed on the remote Windows host is prior to 26.01. It is, therefore, affected by a
vulnerability:

  - A heap buffer overflow vulnerability exists in the NTFS archive handler. The CInStream::GetCuSize() function
    computes the compression-unit buffer size using a 32-bit shift that reaches undefined behavior when
    ClusterSizeLog >= 28 and CompressionUnit == 4, causing _inBuf to be allocated as 1 byte. ReadStream_FALSE
    then writes up to 256 MB of attacker-controlled data into this buffer, leading to a vtable hijack and
    potential arbitrary code execution. (CVE-2026-48095)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://securitylab.github.com/advisories/GHSL-2026-140_7-Zip/");
  script_set_attribute(attribute:"see_also", value:"https://sourceforge.net/p/sevenzip/discussion/45797/thread/555e132ba4");
  script_set_attribute(attribute:"solution", value:
"Upgrade to 7-Zip version 26.01 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:POC/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2026-48095");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2026/05/22");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/04/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/07/17");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:7-zip:7-zip");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Windows");

  script_copyright(english:"This script is Copyright (C) 2026 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("7zip_installed.nbin");
  script_require_keys("installed_sw/7-Zip");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'requires': [
    {'scope': 'target', 'match': {'os': 'windows'}}
  ],
  'checks': [
    {
      'product': {'name': '7-Zip', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        {'fixed_version': '26.01'}
      ]
    }
  ]
};

var result = vdf::check_and_report(vuln_data:vuln_data, severity:SECURITY_HOLE);
vdf::handle_check_and_report_errors(vdf_result:result);