Anthropic Claude Code < 2.0.65 API Key Leak via Project Settings (CVE-2026-21852)

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

include('compat.inc');

if (description)
{
  script_id(305985);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2026/04/13");

  script_cve_id("CVE-2026-21852");
  script_xref(name:"IAVA", value:"2026-A-0304");

  script_name(english:"Anthropic Claude Code < 2.0.65 API Key Leak via Project Settings (CVE-2026-21852)");

  script_set_attribute(attribute:"synopsis", value:
"An application installed on the remote host is affected by an
information disclosure vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Anthropic Claude Code installed on the remote host is
prior to 2.0.65. It is, therefore, affected by an information
disclosure vulnerability.

A vulnerability in the project-load flow allowed malicious
repositories to exfiltrate data including Anthropic API keys before
users confirmed trust. If a user started Claude Code in an
attacker-controlled repository, and the repository included a settings
file that set ANTHROPIC_BASE_URL to an attacker-controlled endpoint,
Claude Code would issue API requests before showing the trust prompt,
potentially leaking the user's API keys. (CVE-2026-21852)

Note that Nessus has not tested for this issue but has instead relied
only on the application's self-reported version number.");
  # https://github.com/anthropics/claude-code/security/advisories/GHSA-jh7p-qr78-84p7
  script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?7b2164da");
  script_set_attribute(attribute:"solution", value:
"Upgrade Anthropic Claude Code to version 2.0.65 or later.");
  script_set_attribute(attribute:"agent", value:"unix");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N");
  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:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss4_vector", value:"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/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-2026-21852");

  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:"2026/01/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2026/01/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2026/04/10");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:anthropic:claude_code");
  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("anthropic_claude_code_nix_installed.nbin");
  script_require_keys("installed_sw/Anthropic Claude Code");

  exit(0);
}

include('vdf.inc');

# @tvdl-content
var vuln_data = {
  'metadata': {'spec_version': '1.0'},
  'checks': [
    {
      'product': {'name': 'Anthropic Claude Code', 'type': 'app'},
      'check_algorithm': 'default',
      'constraints': [
        {
          'fixed_version': '2.0.65'
        }
      ]
    }
  ]
};

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