CVE-2026-34450

Claude SDK for Python: Insecure Default File Permissions in Local Filesystem Memory Tool

State
Published
Severity
4.8 Medium
Published
Mar 31, 2026
Updated
Apr 1, 2026
Reserved
Mar 27, 2026

Read the record on cve.org

Description

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.

Scores

CVSSScoreVectorSource
4.04.8 MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NGitHub_M

Weaknesses

  • CWE-276 Incorrect Default Permissions
  • CWE-732 Incorrect Permission Assignment for Critical Resource

Affected Products

ProductVersions
anthropic-sdk-pythonanthropics
  • >= 0.86.0, < 0.87.0Affected

References

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