What is CVE-2026-42906?

CVE-2026-42906 is a medium-severity vulnerability in Microsoft Windows_10_21h2, classified under Information Disclosure. CVSS score: 5.5/10. Published 2026-06-09.

How severe is CVE-2026-42906?

Medium severity. CVSS v3 base score is 5.5 out of 10.

Information disclosure in Microsoft Windows_10_21h2

CVE-2026-42906

Exposure of sensitive information to an unauthorized actor in Windows Shell allows an authorized attacker to disclose information locally.

Vulnerability class: Information Disclosure

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Microsoft Windows_10_21h2
Microsoft Windows_10_22h2
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-200 — Information Disclosure

References

secure@microsoft.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-42906?: CVE-2026-42906 is a medium-severity vulnerability in Microsoft Windows_10_21h2, classified under Information Disclosure. CVSS score: 5.5/10. Published 2026-06-09.
How severe is CVE-2026-42906?: Medium severity. CVSS v3 base score is 5.5 out of 10.