Vulnerability in Anthropic Claude Code
CVE-2026-25725
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.
EPSS: 0.005 (39.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H.
Affected products
- Anthropic Claude_code
- Anthropics Claude-code — versions < 2.1.2
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-25725?
- CVE-2026-25725 is a critical-severity vulnerability in Anthropic Claude Code, classified under Trust Boundary Violation. CVSS score: 10.0/10. Published 2026-02-06.
- How severe is CVE-2026-25725?
- Critical severity. CVSS v3 base score is 10.0 out of 10.