AnthropicGHSA-p7fg-763f-g4gf
Claude SDK for TypeScript has Insecure Default File Permissions in Local Filesystem Memory Tool
Medium4.8CVE-2026-41686 · Published Apr 24, 2026
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. Users on the affected versions are advised to update to the latest version. Thank you `lucasfutures` for the report.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| @anthropic-ai/sdk npm | >= 0.79.0, < 0.91.1 | 0.91.1 |
Details and references
- CVSS 4.0
- CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
- Severity from
- GitHub (reviewed advisory)
- Weakness
- CWE-732
More Anthropic advisories
All Anthropic| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| May 6 | SSH Host Key Verification Bypass Allows Man-in-the-Middle Attack on Remote Sessions | High7.4 | 1.4304.0 |
| May 6 | Local Privilege Escalation via Directory Junction in CoworkVMService | High8.5 | 1.3834.0 |
| Apr 24 | Trust Dialog Bypass via Git Worktree Spoofing Allows Arbitrary Code Execution | High7.7 | 2.1.84 |
| Apr 20 | Sandbox Escape via Symlink Following Allows Arbitrary File Write Outside Workspace | High7.7 | 2.1.64 |
| Apr 17 | Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on Windows | Medium5.4 | 2.1.75 |
| Mar 31 | Memory Tool Path Validation Race Condition Allows Sandbox Escape | Medium5.8 | 0.87.0 |