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CVE

CVE-2026-25725

Claude Code Has Sandbox Escape via Persistent Configuration Injection in settings.json
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CVE

CVE-2026-25725

Claude Code Has Sandbox Escape via Persistent Configuration Injection in settings.json

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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
7.7
-
4.0
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25725.json, https://github.com/anthropics/claude-code/security/advisories/GHSA-ff64-7w26-62rf, https://nvd.nist.gov/vuln/detail/CVE-2026-25725

Severity

0

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
0
EPSS Probability
0.00061%
EPSS Percentile
0.18869%
Introduced Version
0
Fix Available
553d6ffc3e2a2b719c501d56a062560c5ce23b54

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