CVE-2026-40378
HIGHDescription
Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.
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CVSS v3.1 Score
EPSS — Exploit Prediction
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)
Affected Products
| Vendor | Product |
|---|---|
| microsoft | windows_10_1607 |
| microsoft | windows_10_1607 |
| microsoft | windows_10_1809 |
| microsoft | windows_10_1809 |
| microsoft | windows_10_21h2 |
| microsoft | windows_10_21h2 |
| microsoft | windows_10_21h2 |
| microsoft | windows_10_22h2 |
| microsoft | windows_10_22h2 |
| microsoft | windows_10_22h2 |
| microsoft | windows_11_23h2 |
| microsoft | windows_11_23h2 |
| microsoft | windows_11_24h2 |
| microsoft | windows_11_24h2 |
| microsoft | windows_11_25h2 |
| microsoft | windows_11_25h2 |
| microsoft | windows_11_26h1 |
| microsoft | windows_11_26h1 |
| microsoft | windows_server_2012 |
| microsoft | windows_server_2012 |
| microsoft | windows_server_2016 |
| microsoft | windows_server_2019 |
| microsoft | windows_server_2022 |
| microsoft | windows_server_2025 |
References
Advisories & Patches
Frequently Asked Questions
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