Allocation of Resources Without Limits or Throttling Affecting anyio package, versions [,4.14.2)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published20 Sept 2026
- disclosed18 Sept 2026
- creditUnknown
Introduced: 18 Sep 2026
NewCVE-2026-64847 (opens in a new tab)How to fix?
Upgrade anyio to version 4.14.2 or higher.
Overview
anyio is a High level compatibility layer for multiple asynchronous event loop implementations
Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling in process_worker within src/anyio/to_process.py, where stderr in a worker subprocess is left connected to the parent process pipe rather than redirected to /dev/null. When worker code writes to stderr, the write can block indefinitely waiting for the parent to drain the pipe, causing a deadlock that crashes the worker and renders it unresponsive.