CVE-2026-45638

highCVSS 7.8covered by 1 sourcefirst seen 2026-06-09

Heap-based buffer overflow in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

CSIRTS triage

What: A heap-based buffer overflow allows an authorized attacker to elevate privileges locally.
Who is affected: Authorized users of Windows Ancillary Function Driver for WinSock.
Urgency: Remediation is high urgency due to the potential for privilege escalation.
Action: Apply the latest security patches for Windows.

AI-assisted analysis generated from the source advisory — verify against the original.

⚡ Watch CVE-2026-45638

Get an email if CVE-2026-45638 is added to CISA KEV, gains public exploit code, or a new advisory cites it — max one per day, one-click unsubscribe.

Low exploitation risk0.29% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 21% of all EPSS-scored CVEs.

— this badge updates automatically when the KEV or exploit status changes. How to embed it →

[![CVE-2026-45638 status](https://www.csirts.com/badge/CVE-2026-45638)](https://www.csirts.com/cve/CVE-2026-45638)