The Claude SDK for Python provides access to the Claude API from Python applications.
Date: 2026-03
Affected: anthropic/claude_sdk_for_python
Attack vector: path-traversal
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2026-34450
CVE-2026-34452
CWE: CWE-276
CWE-367
CWE-59
CWE-732
CVSS: 4.4 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)

The Claude SDK for Python provides access to the Claude API from Python applications. From version 0.86.0 to before version 0.87.0, the local filesystem memory tool in the Anthropic Python SDK created memory files with mode 0o666, 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. Both the synchronous and asynchronous memory tool implementations were affected. This issue has been patched in version 0.87.0.


Mitigations:

Architectural layers (MAESTRO):