CVE-2026-41686: anthropic claude_sdk_for_typescript

Vulnerability summary

CVE-2026-41686 is a medium (CVSS 4.8) vulnerability in anthropic claude_sdk_for_typescript. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2.1% of scored vulnerabilities.

Timeline

1. 04-05-2026
   PublishedVulnerability first disclosed.
2. 05-05-2026
   Last modifiedVulnerability information updated.

Description

Claude SDK for TypeScript provides access to the Claude API from server-side TypeScript or JavaScript applications. From version 0.79.0 to before version 0.91.1, the BetaLocalFilesystemMemoryTool in the Anthropic TypeScript SDK created memory files and directories using the Node.js default modes (0o666 for files, 0o777 for directories), leaving them world-readable on systems with a standard umask and world-writable in environments with a permissive umask such as many Docker base images. A local attacker on a shared host could read persisted agent state, and in containerized deployments could modify memory files to influence subsequent model behavior. This issue has been patched in version 0.91.1.

• CWE-732Incorrect Permission Assignment for Critical ResourceThe product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.