CVE-2026-41686: CWE-732: Incorrect Permission Assignment for Critical Resource in anthropics anthropic-sdk-typescript
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.
AI Analysis
Technical Summary
CVE-2026-41686 is a vulnerability in the anthropic-sdk-typescript package affecting versions 0.79.0 through 0.91.0. The BetaLocalFilesystemMemoryTool component used Node.js default file and directory modes (0o666 for files, 0o777 for directories), which are too permissive on systems with standard or permissive umasks. This incorrect permission assignment (CWE-732) can lead to unauthorized local read access to agent state and unauthorized modification in containerized deployments. The vulnerability is patched in version 0.91.1.
Potential Impact
Local attackers on shared hosts can read sensitive persisted agent state due to world-readable files. In containerized environments with permissive umasks, attackers can modify memory files, potentially influencing the behavior of the AI model. There is no indication of remote exploitation or privilege escalation beyond local access. The CVSS 4.8 (medium severity) reflects the local attack vector and required privileges.
Mitigation Recommendations
Upgrade to anthropic-sdk-typescript version 0.91.1 or later, where the issue is patched. No other mitigation is indicated or necessary as the vulnerability is resolved in the fixed version.
CVE-2026-41686: CWE-732: Incorrect Permission Assignment for Critical Resource in anthropics anthropic-sdk-typescript
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-41686 is a vulnerability in the anthropic-sdk-typescript package affecting versions 0.79.0 through 0.91.0. The BetaLocalFilesystemMemoryTool component used Node.js default file and directory modes (0o666 for files, 0o777 for directories), which are too permissive on systems with standard or permissive umasks. This incorrect permission assignment (CWE-732) can lead to unauthorized local read access to agent state and unauthorized modification in containerized deployments. The vulnerability is patched in version 0.91.1.
Potential Impact
Local attackers on shared hosts can read sensitive persisted agent state due to world-readable files. In containerized environments with permissive umasks, attackers can modify memory files, potentially influencing the behavior of the AI model. There is no indication of remote exploitation or privilege escalation beyond local access. The CVSS 4.8 (medium severity) reflects the local attack vector and required privileges.
Mitigation Recommendations
Upgrade to anthropic-sdk-typescript version 0.91.1 or later, where the issue is patched. No other mitigation is indicated or necessary as the vulnerability is resolved in the fixed version.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-22T03:53:24.406Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69f8eaaecbff5d8610415ae9
Added to database: 5/4/2026, 6:51:26 PM
Last enriched: 5/4/2026, 7:07:25 PM
Last updated: 5/5/2026, 5:55:01 AM
Views: 12
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