CVE-2026-55607

HIGH CVSS 4.0: 7.7 EPSS 0.55%
Updated Jun 30, 2026
Anthropic
Parameter Value
CVSS 7.7 (HIGH)
Affected Versions 2.1.38 — 2.1.163
Fixed In 2.1.163
Type CWE-59 (Improper Link Resolution), CWE-22 (Path Traversal), CWE-78 (OS Command Injection)
Vendor Anthropic
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
Passive
Minimal interaction

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service

CVSS Vector v4.0

Vulnerable Products 1

Configuration From (including) Up to (excluding)
Anthropic Claude_Code
cpe:2.3:a:anthropic:claude_code:*:*:*:*:*:node.js:*:*
2.1.38 2.1.163