CVE-2026-45657

CRITICAL

Published Jun 9, 2026 Modified Jun 10, 2026 CWE-122 CWE-416

Description

Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network.

CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.1548

Probability of exploitation

0.96%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-122 CWE-122

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
microsoft	windows_11_23h2	< 10.0.22631.7219
microsoft	windows_11_23h2	< 10.0.22631.7219
microsoft	windows_11_24h2	< 10.0.26100.8655
microsoft	windows_11_24h2	< 10.0.26100.8655
microsoft	windows_11_25h2	< 10.0.26200.8655
microsoft	windows_11_25h2	< 10.0.26200.8655
microsoft	windows_11_26h1	< 10.0.28000.2269
microsoft	windows_11_26h1	< 10.0.28000.2269
microsoft	windows_server_2022	< 10.0.20348.5256
microsoft	windows_server_2025	< 10.0.26100.32995

References

Advisories & Patches

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-45657

Frequently Asked Questions

What is CVE-2026-45657? +

Use after free in Windows Kernel allows an unauthorized attacker to execute code over a network. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-45657? +

CVE-2026-45657 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.1548, placing it in the 1th percentile for exploitation probability.

What products are affected by CVE-2026-45657? +

CVE-2026-45657 affects products from microsoft, specifically: windows_11_23h2, windows_11_24h2, windows_11_25h2, windows_11_26h1, windows_server_2022, windows_server_2025. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-45657? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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