Vulnerability in Anthropic Claude Code
CVE-2026-35603
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.
EPSS: 0.001 (1.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H.
Affected products
- Anthropic Claude_code
- Anthropics Claude-code — versions < 2.1.75
- Microsoft Windows
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-35603?
- CVE-2026-35603 is a high-severity vulnerability in Anthropic Claude Code, classified under Untrusted Search Path. CVSS score: 7.3/10. Published 2026-04-17.
- How severe is CVE-2026-35603?
- High severity. CVSS v3 base score is 7.3 out of 10.
- Is CVE-2026-35603 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.