CVE-2025-21418 — Microsoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerability
CVE-2025-21418: Microsoft Windows Ancillary Function Driver for WinSock Heap-Based Buffer Overflow Vulnerability
CISA Known Exploited Vulnerability (KEV)
| Vendor / project | Microsoft |
| Product | Windows |
| Date added | 2025-02-11 |
| Due date | 2025-03-04 |
| Ransomware campaign use | Unknown |
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 (CISA)
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
References
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-21418
- KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog