# CVE-2025-48945: pycares: pycares is a Python module which provides an interface to c-ares

CVE-2025-48945 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2025-48945, released June 20, 2025. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2025-48945
- Priority: Routine
- CVSS: n/a
- EPSS: 0.0048
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jun 20, 2025

## Description

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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | pycares Debian 14 | 4.9.0-1 | [DEBIAN-CVE-2025-48945](https://patchblox.com/security/data/fix/linux/debian-cve-2025-48945.md) | Jun 20, 2025 |
| Linux | python-pycares opensuse-leap 15.6 | 4.10.0-150400.9.8.1 | [SUSE-SU-2025:03354-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03354-1.md) | Sep 25, 2025 |
| Linux | python-pycares sles 15.6 | 4.10.0-150400.9.8.1 | [SUSE-SU-2025:03354-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03354-1.md) | Sep 25, 2025 |
| Linux | python-pycares sles 15.7 | 4.10.0-150400.9.8.1 | [SUSE-SU-2025:03354-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-03354-1.md) | Sep 25, 2025 |

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Data as of 2026-11-08T00:53:09Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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