CVE-2026-35603: Claude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows

Vulnerability summary

CVE-2026-35603 is a high (CVSS 7.3) Untrusted Search Path vulnerability in anthropic claude_code. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.9% of scored vulnerabilities.

Timeline

1. 17-04-2026
   PublishedVulnerability first disclosed.
2. 20-04-2026
   Last modifiedVulnerability information updated.

Description

Claude Code is an agentic coding tool. In versions prior to 2.1.75 on Windows, Claude Code loaded the 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. This issue has been fixed on version 2.1.75.

• CWE-426Untrusted Search PathThe product searches for critical resources using an externally-supplied search path that can point to resources that are not under the product's direct control.