Summaryinfo

A vulnerability was found in Anthropic anthropic-sdk-python up to 0.86.x. It has been rated as critical. Impacted is an unknown function of the component Claude API. The manipulation leads to default permission. This vulnerability is uniquely identified as CVE-2026-34450. Local access is required to approach this attack. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Anthropic anthropic-sdk-python up to 0.86.x. This issue affects an unknown function of the component Claude API. The manipulation with an unknown input leads to a default permission vulnerability. Using CWE to declare the problem leads to CWE-276. During installation, installed file permissions are set to allow anyone to modify those files. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-34450 since 03/27/2026. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1222 for this issue.

Upgrading to version 0.87.0 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 715030ceb4d6dd8d3546e999c680e29532bf1255 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Artificial Intelligence Software

Vendor

• Anthropic

Name

• anthropic-sdk-python

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

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Entryinfo

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