CVE-2025-48945

pycares has a Use-After-Free Vulnerability

HIGH
8.2
CVSS Score
Published: June 20, 2025 at 07:14 PM UTC
Updated: June 17, 2026 at 09:30 AM UTC
1 product affected across 1 vendorAiodns

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Severity
HIGH8.2
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.9.0
Affected range stops below 4.9.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.2HIGHGitHub_M
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-416

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