Microsoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerability
Microsoft — Windows
- Added to KEV catalog
- 11 February 2025
- Federal remediation due date
- 4 March 2025
- Weakness classification (CWE)
- CWE-122
CISA 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.
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Notes
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-21418 ; https://nvd.nist.gov/vuln/detail/CVE-2025-21418
More Microsoft Vulnerabilities
Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
Microsoft Windows Buffer Overflow Vulnerability
Microsoft DirectX NULL Byte Overwrite Vulnerability
Microsoft Internet Explorer Use-After-Free Vulnerability
Microsoft Internet Explorer Use-After-Free Vulnerability
Is this vulnerability present in your environment?
CRS delivers independent VAPT assessments that identify exactly which known-exploited vulnerabilities exist in your network, applications, and infrastructure.
Explore VAPT Services