Claude Code — Prompt Injection (CVE-2026-55607)
Date: 2026-06
Affected: anthropic/claude_code
Attack vector: prompt-injection
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2026-55607
CWE: CWE-22
CWE-59
CWE-78
CVSS: 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Claude Code is an agentic coding tool. From 2.1.38 until 2.1.163, Claude Code's worktree handling allowed creation of worktrees named ".git" and navigation to worktrees outside the sandbox context, enabling git directory confusion attacks. By exploiting symlink manipulation and git fsmonitor execution during worktree operations, an attacker could overwrite files in the user's home directory (such as .zshenv), leading to code execution outside of seatbelt sandbox restrictions. Reliably exploiting this required the user to clone a malicious repository containing prompt injection content and run Claude Code against it. This vulnerability is fixed in 2.1.163.


Mitigations:

Architectural layers (MAESTRO):