Use After Free Affecting pycares package, versions *


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

EPSS
0.06% (19th percentile)

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  • Snyk IDSNYK-DEBIANUNSTABLE-PYCARES-10389902
  • published19 Jun 2025
  • disclosed20 Jun 2025

Introduced: 19 Jun 2025

NewCVE-2025-48945  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

There is no fixed version for Debian:unstable pycares.

NVD Description

Note: Versions mentioned in the description apply only to the upstream pycares package and not the pycares package as distributed by Debian. See How to fix? for Debian:unstable relevant fixed versions and status.

pycares is a Python module which provides an interface to c-ares. c-ares is a C library that performs DNS requests and name resolutions asynchronously. Prior to version 4.9.0, pycares is vulnerable to a use-after-free condition that occurs when a Channel object is garbage collected while DNS queries are still pending. This results in a fatal Python error and interpreter crash. The vulnerability has been fixed in pycares 4.9.0 by implementing a safe channel destruction mechanism.

CVSS Base Scores

version 3.1