Anthropic anthropic-sdk-typescript up to 0.91.0 Claude API permission assignment

Summaryinfo

A vulnerability identified as problematic has been detected in Anthropic anthropic-sdk-typescript up to 0.91.0. This affects an unknown part of the component Claude API. The manipulation leads to permission assignment. This vulnerability is referenced as CVE-2026-41686. The attack can only be performed from a local environment. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Anthropic anthropic-sdk-typescript up to 0.91.0. This issue affects some unknown functionality of the component Claude API. The manipulation with an unknown input leads to a permission assignment vulnerability. Using CWE to declare the problem leads to CWE-732. The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-41686 since 04/22/2026. The exploitation is known to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 0.91.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-27087). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• Anthropic

Name

• anthropic-sdk-typescript

Version

• 0.1
• 0.2
• 0.3
• 0.4
• 0.5
• 0.6
• 0.7
• 0.8
• 0.9
• 0.10
• 0.11
• 0.12
• 0.13
• 0.14
• 0.15
• 0.16
• 0.17
• 0.18
• 0.19
• 0.20
• 0.21
• 0.22
• 0.23
• 0.24
• 0.25
• 0.26
• 0.27
• 0.28
• 0.29
• 0.30
• 0.31
• 0.32
• 0.33
• 0.34
• 0.35
• 0.36
• 0.37
• 0.38
• 0.39
• 0.40
• 0.41
• 0.42
• 0.43
• 0.44
• 0.45
• 0.46
• 0.47
• 0.48
• 0.49
• 0.50
• 0.51
• 0.52
• 0.53
• 0.54
• 0.55
• 0.56
• 0.57
• 0.58
• 0.59
• 0.60
• 0.61
• 0.62
• 0.63
• 0.64
• 0.65
• 0.66
• 0.67
• 0.68
• 0.69
• 0.70
• 0.71
• 0.72
• 0.73
• 0.74
• 0.75
• 0.76
• 0.77
• 0.78
• 0.79
• 0.80
• 0.81
• 0.82
• 0.83
• 0.84
• 0.85
• 0.86
• 0.87
• 0.88
• 0.89
• 0.90
• 0.91.0

CPE 2.3info

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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