Exploited vulnerability

CVE-2025-21418

TLP:CLEAR

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

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.

Facts

Vendor: Microsoft
Product: Windows
CVSS: 7.8
EPSS (probability of exploitation within 30 days): 2.1 %
On CISA's Known Exploited Vulnerabilities list since: 11 February 2025
First known exploitation: 11 February 2025
CISA's deadline for US federal agencies: 4 March 2025
Weakness: CWE-122
First seen by Risk Letters: 11 February 2025

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD