What is CVE-2026-45603?

CVE-2026-45603 is a high-severity vulnerability, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.0/10. Published 2026-06-09.

How severe is CVE-2026-45603?

High severity. CVSS v3 base score is 7.0 out of 10.

CVE-2026-45603

CVE-2026-45603

Use after free in Windows Ancillary Function Driver for WinSock allows an authorized attacker to elevate privileges locally.

Vulnerability class: Race Condition

CVSS v3 metric

CVSS v3 base score 7.0 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H.

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

secure@microsoft.com

Frequently asked questions

What is CVE-2026-45603?: CVE-2026-45603 is a high-severity vulnerability, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.0/10. Published 2026-06-09.
How severe is CVE-2026-45603?: High severity. CVSS v3 base score is 7.0 out of 10.