CVE-2025-21418HIGH 7.8CISA KEVEPSS p70.1%

CVE-2025-21418Microsoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerability

Microsoft / Windows

Description

Microsoft Windows Ancillary Function Driver for WinSock contains a heap-based buffer overflow vulnerability that allows for privilege escalation, enabling a local attacker to gain SYSTEM privileges.

Scoring

CVSS 3.17.8 (HIGH)
VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS1.46% probability of exploitation · percentile 70.1% · 2026-06-18T12:00:27Z
Published2025-02-11
Last modified2025-10-27

CISA KEV entry

Added to KEV: 2025-02-11

Underlying weaknesses· 1

CWE-122

References

  1. https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21418
  2. https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-21418

1

TypeTargetConfidenceTier
WeaknessHeap-based Buffer Overflowcwe-1220%live

(incoming)1

TypeTargetConfidenceTier
KEVEntryMicrosoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerabilitykev-cve-2025-214180%live

Related by meaning· 6

Nearest entities by semantic similarity across the cs-graph corpus.

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Microsoft Windows Ancillary Function Driver for WinSock Privilege Escalation Vulnerability
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Microsoft Windows Ancillary Function Driver for WinSock Use-After-Free Vulnerability
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Sourced from NVD + CISA KEV + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.