GitHub Advisoryadvisory · npm
GHSA-jh7p-qr78-84p7 Claude Code Leaks Data via Malicious Environment Configuration Before Trust Confirmation
MEDIUM
Official page ↗
- Aliases
- CVE-2026-21852
- Ecosystem
- npm
- Packages
- @anthropic-ai/claude-code
- Severity
- Moderate
- CVSS vector
- CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
- Weaknesses
- CWE-522
- Reviewed
- 2026-01-21
Affected packages
• npm @anthropic-ai/claude-code: < 2.0.65 → fixed in 2.0.65
Description
A vulnerability in Claude Code's project-load flow allowed malicious repositories to exfiltrate data including Anthropic API keys before users confirmed trust. If a user started Claude Code in an attacker-controller repository, and the repository included a settings file that set ANTHROPIC_BASE_URL to an attacker-controlled endpoint, Claude Code would issue API requests before showing the trust prompt, including potentially leaking the user's API keys.
Users on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.
Related
Alias · CVE (1)
- CVE-2026-21852 Claude Code is an agentic coding tool. vulnerability
Weakness · CWE (1)
- CWE-522 Insufficiently Protected Credentials weakness