PyPI: anyio

SFTY-20240526-99260

Safety legacy ID: pyup.io-71199

Anyio version 4.4.0 addresses a thread race condition in `_eventloop.get_asynclib()` that caused crashes when multiple event loops of the same backend were running in separate threads and simultaneously attempted to use AnyIO for the first time. This fix ensures more stable and reliable performance in multi-threaded environments.

PythonPyPI
Created at: Nov 5, 2025Updated at: Nov 5, 2025

Overview

Anyio version 4.4.0 addresses a thread race condition in `_eventloop.get_asynclib()` that caused crashes when multiple event loops of the same backend were running in separate threads and simultaneously attempted to use AnyIO for the first time. This fix ensures more stable and reliable performance in multi-threaded environments.

Advisory

Anyio version 4.4.0 addresses a thread race condition in `_eventloop.get_asynclib()` that caused crashes when multiple event loops of the same backend were running in separate threads and simultaneously attempted to use AnyIO for the first time. This fix ensures more stable and reliable performance in multi-threaded environments.

Affected Package

Affecting anyio package, versions
<4.4.0

Also affects

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How to Fix

Upgrade
anyio
to
4.4.0
or higher.

Mitigation and Workarounds

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Vulnerable Functions

Functions linked to known vulnerabilities.

Vulnerable function data is available for Enterprise customers

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References

Safety

Verified by Safety

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