Medium 5.8Published Mar 31, 2026

CVE-2026-34452Claude SDK for Python: Memory Tool Path Validation Race Condition Allows Sandbox Escape

Updated under an hour ago (Oct 27, 2026, 4:30 PM ET)

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Every CVE for anthropics anthropic-sdk-python

Exploited in the last 30 days

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.

CVSS: 5.8 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
Weakness (CWE): CWE-59, CWE-367
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 3, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

anthropics anthropic-sdk-python anthropics:anthropic_sdk_python (from the name)	from 0.86.0, < 0.87.0	CNA record
anthropic claude_sdk_for_python anthropic:claude_sdk_for_python	from 0.86.0 before 0.87.0	NVD

References

References

https://github.com/anthropics/anthropic-sdk-python/security/advisories/GHSA-w828-4qhx-vxx3	x-refsource-confirm, vendor-advisory
https://github.com/anthropics/anthropic-sdk-python/commit/6599043eee6e86dce16953fcd1fd828052052be6	x-refsource-misc, patch
https://github.com/anthropics/anthropic-sdk-python/releases/tag/v0.87.0	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.