Summaryinfo

A vulnerability has been found in Anthropic anthropic-sdk-python up to 0.86.x and classified as critical. Affected by this issue is some unknown functionality of the component Claude API. This manipulation causes link following. This vulnerability appears as CVE-2026-34452. The attack requires local access. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Anthropic anthropic-sdk-python up to 0.86.x. It has been declared as critical. Affected by this vulnerability is an unknown part of the component Claude API. The manipulation with an unknown input leads to a link following vulnerability. The CWE definition for the vulnerability is CWE-59. The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource. As an impact it is known to affect 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 async local filesystem memory tool in the Anthropic Python SDK validated that model-supplied paths resolved inside the sandboxed memory directory, but then returned the unresolved path for subsequent file operations. A local attacker able to write to the memory directory could retarget a symlink between validation and use, causing reads or writes to escape the sandbox. The synchronous memory tool implementation was not affected. This issue has been patched in version 0.87.0.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-34452 since 03/27/2026. The exploitation appears to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

Upgrading to version 0.87.0 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 6599043eee6e86dce16953fcd1fd828052052be6 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.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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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