CVE-2026-25725 HIGH

CVE-2026-25725: Claude Code Has Sandbox Escape via Persistent Configuration Injection in settings.json

Vendor Anthropics
Product claude-code
Weakness CWE-501
Published February 6, 2026
Last update February 6, 2026

CVSS base score

7.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Claude Code is an agentic coding tool. Prior to version 2.1.2, Claude Code's bubblewrap sandboxing mechanism failed to properly protect the .claude/settings.json configuration file when it did not exist at startup. While the parent directory was mounted as writable and .claude/settings.local.json was explicitly protected with read-only constraints, settings.json was not protected if it was missing. This allowed malicious code running inside the sandbox to create this file and inject persistent hooks (such as SessionStart commands) that would execute with host privileges when Claude Code was restarted. This issue has been patched in version 2.1.2.

Key dates

02Disclosure timeline

February 6, 2026 CVE published
February 6, 2026 Record updated