GHSA-5CWG-9F6J-9JVX

Vulnerability from github – Published: 2026-04-17 22:19 – Updated: 2026-04-17 22:19
VLAI?
Summary
Claude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows
Details

On Windows, Claude Code loaded system-wide default configuration from C:\ProgramData\ClaudeCode\managed-settings.json without validating directory ownership or access permissions. Because the ProgramData directory is writable by non-administrative users by default and the ClaudeCode subdirectory was not pre-created or access-restricted, a low-privileged local user could create this directory and place a malicious configuration file that would be automatically loaded for any user launching Claude Code on the same machine. Exploiting this would have required a shared multi-user Windows system and a victim user to launch Claude Code after the malicious configuration was placed.

Users on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.

Thank you to hackerone.com/edbr for reporting this issue.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@anthropic-ai/claude-code"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.75"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-35603"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-426"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-17T22:19:38Z",
    "nvd_published_at": "2026-04-17T21:16:33Z",
    "severity": "MODERATE"
  },
  "details": "On Windows, Claude Code loaded system-wide default configuration from `C:\\ProgramData\\ClaudeCode\\managed-settings.json` without validating directory ownership or access permissions. Because the `ProgramData` directory is writable by non-administrative users by default and the `ClaudeCode` subdirectory was not pre-created or access-restricted, a low-privileged local user could create this directory and place a malicious configuration file that would be automatically loaded for any user launching Claude Code on the same machine. Exploiting this would have required a shared multi-user Windows system and a victim user to launch Claude Code after the malicious configuration was placed.\n\nUsers on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.\n\nThank you to hackerone.com/edbr for reporting this issue.",
  "id": "GHSA-5cwg-9f6j-9jvx",
  "modified": "2026-04-17T22:19:38Z",
  "published": "2026-04-17T22:19:38Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/anthropics/claude-code/security/advisories/GHSA-5cwg-9f6j-9jvx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35603"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/anthropics/claude-code"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Claude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows"
}


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