CVE-2026-34452 Claude SDK for Python: Memory Tool Path Validation Race Condition Allows Sandbox Escape
A race condition in the Claude Python SDK allows local attackers to escape the sandbox via symlink manipulation, enabling unauthorized file access.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-34452?
CVE-2026-34452 is a medium-severity vulnerability in anthropics anthropic-sdk-python, published on 31 Mar 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Which versions are affected by CVE-2026-34452?
3 open source packages ship an affected version, including anthropic. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
anthropic PyPI | From 0.86.0 | 0.87.0 |
anthropic PyPI | From 0.86.0 | 0.87.0 |
anthropic PyPI | From 0.86.0 | 0.87.0 |
Products include Anthropic Claude Sdk for Python.
How do I fix CVE-2026-34452?
Upgrade anthropic to 0.87.0 or later.
Is CVE-2026-34452 being exploited?
There is no known exploitation of CVE-2026-34452 in the wild and no public exploit code.
Other vulnerabilities in anthropics anthropic-sdk-python
Sources
Also known as ECHO-38d5-c884-2737, GHSA-w828-4qhx-vxx3, PYSEC-2026-2115.