CVE-2026-35603: Claude Code Insecure Configuration Loading LPE

# CVE-2026-35603: Claude Code Insecure Configuration Loading LPE

https://gcdradar.vercel.app/incidents/cve-2026-35603-claude-code-insecure-configuration-loading-lp · AIR-2026-0589 · closed 2026-04-17

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-04-17
- AI role: Attack on AI
- Products: Claude Code
- CVE ids: CVE-2026-35603
- CVSS: 7.3

## Summary

Claude Code on Windows loaded system-wide configuration files without validating directory ownership. This allowed low-privileged local users to create malicious configuration files and execute code.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-04-17: CVE-2026-35603: Claude Code is an agentic coding tool. (https://nvd.nist.gov/vuln/detail/CVE-2026-35603)
- 2026-04-17: CVE-2026-35603: Claude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows (https://github.com/advisories/GHSA-5cwg-9f6j-9jvx)

## Sources

- 2026-04-17 GitHub Advisory Database: CVE-2026-35603: Claude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows https://github.com/advisories/GHSA-5cwg-9f6j-9jvx
- 2026-04-17 NVD: CVE-2026-35603: Claude Code is an agentic coding tool. https://nvd.nist.gov/vuln/detail/CVE-2026-35603

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.