CVE-2026-35603
7.3 · HIGHOverview
CVE-2026-35603 is a high-severity vulnerability affecting anthropic claude_code. It was published on April 17, 2026 and has a CVSS 3.1 base score of 7.3 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.3, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from anthropic. Update claude_code to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| anthropic | claude_code | >= 0, < 2.1.75 | Affected |
Frequently Asked Questions
What is CVE-2026-35603?
CVE-2026-35603 is a high-severity vulnerability affecting anthropic claude_code. It was published on April 17, 2026 and has a CVSS 3.1 base score of 7.3 (HIGH).
How severe is CVE-2026-35603?
This vulnerability has a CVSS 3.1 base score of 7.3, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-35603?
Check the references section for vendor advisories and patches from anthropic. Update claude_code to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-35603?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-35603 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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