Directory and File Permissions Vulnerability in Claude SDK for TypeScript
CVE-2026-41686

4.8MEDIUM

Key Information:

Vendor

Anthropics

Status
Anthropic-sdk-typescript
Vendor
CVE Published:
4 May 2026

What is CVE-2026-41686?

The Claude SDK for TypeScript, which facilitates access to the Claude API, contains a vulnerability in the BetaLocalFilesystemMemoryTool. This issue affects versions from 0.79.0 to before 0.91.1. Due to improper file and directory permissions, specified as Node.js default modes (0o666 for files and 0o777 for folders), these files and directories become world-readable and, in permissive environments like many Docker images, world-writable. Consequently, a local attacker on a shared hosting environment can read sensitive data stored within these memory files and, in containerized applications, potentially alter these files to manipulate model behavior. The vulnerability has been addressed in version 0.91.1.

Affected Version(s)

anthropic-sdk-typescript >= 0.79.0, < 0.91.1

References

https://github.com/anthropics/anthropic-sdk-typescript/se...
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CVSS V4

Score:
4.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
None
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.