CVE-2026-21852 — Claude Code Leaks Data via Malicious Environment Configuration Before Trust Confirmation

Description (CNA)

Claude Code is an agentic coding tool. Prior to version 2.0.65, vulnerability in Claude Code's project-load flow allowed malicious repositories to exfiltrate data including Anthropic API keys before users confirmed trust. An attacker-controlled repository could include a settings file that sets ANTHROPIC_BASE_URL to an attacker-controlled endpoint and when the repository was opened, Claude Code would read the configuration and immediately issue API requests before showing the trust prompt, 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 version 2.0.65, which contains a patch, or to the latest version.

Affected (CNA)

Vendor / product	Versions
anthropics / claude-code	affected < 2.0.65

CWE

CWE-522

References

https://github.com/anthropics/claude-code/security/advisories/GHSA-jh7p-qr78-84p7

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.