Claude Code — Data Exfiltration (CVE-2026-24052)
Date: 2026-02
Affected: anthropic/claude_code
Attack vector: data-exfiltration
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-24052
CWE: CWE-601
CVSS: 7.4 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N)

Claude Code is an agentic coding tool. Prior to version 1.0.111, Claude Code contained insufficient URL validation in its trusted domain verification mechanism for WebFetch requests. The application used a startsWith() function to validate trusted domains (e.g., docs.python.org, modelcontextprotocol.io), this could have enabled attackers to register domains like modelcontextprotocol.io.example.com that would pass validation. This could enable automatic requests to attacker-controlled domains without user consent, potentially leading to data exfiltration. This issue has been patched in version 1.0.111.


Mitigations:

Architectural layers (MAESTRO):