What’s Vulnerable › Vulnerabilities
CVE-2026-25725: Claude Code Has Sandbox Escape via Persistent Configuration Injection in settings.json
- Severity: critical (CVSS 10.0 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-02-06 · updated 2026-06-17
- Weakness: CWE-501
Description
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.
Affected products
- anthropics claude-code: before 2.1.2 — fixed in 2.1.2
How to fix
Upgrade to a fixed version: anthropics claude-code 2.1.2. Check the vendor advisory for mitigations.
References
Get alerted when CVE-2026-25725 or the next vulnerability affects your stack