What is CVE-2026-42981?

CVE-2026-42981 is a high-severity vulnerability in Microsoft Windows_11_23h2, classified under Integer Underflow. CVSS score: 8.1/10. Published 2026-06-09.

How severe is CVE-2026-42981?

High severity. CVSS v3 base score is 8.1 out of 10.

Integer overflow in Microsoft Windows_11_23h2

CVE-2026-42981

Integer underflow (wrap or wraparound) in Windows Performance Monitor allows an unauthorized attacker to execute code over a network.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Microsoft Windows_11_23h2
Microsoft Windows_11_24h2
Microsoft Windows_11_25h2
Microsoft Windows_11_26h1
Microsoft Windows_server_2022
Microsoft Windows_server_2025

Weakness classification (CWE)

CWE-191 — Integer Underflow

References

secure@microsoft.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-42981?: CVE-2026-42981 is a high-severity vulnerability in Microsoft Windows_11_23h2, classified under Integer Underflow. CVSS score: 8.1/10. Published 2026-06-09.
How severe is CVE-2026-42981?: High severity. CVSS v3 base score is 8.1 out of 10.