CVE-2026-40378
Windows Local Security Authority Subsystem Service (LSASS) Denial of Service vulnerability
Microsoft·Windows Local Security Authority Subsystem Service (LSASS) Denial of Service
MSRC advisory July 14, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-40378
- Affected products
- Windows Local Security Authority Subsystem Service (LSASS) Denial of Service · Microsoft Windows Local Security Authority Subsystem Service (LSASS) Denial of Service · Microsoft
What happened
Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network.
What it means for your business
Windows Local Security Authority Subsystem Service (LSASS) Denial of Service vulnerability (CVE-2026-40378) was added to Microsoft’s security update guidance. Memory allocation with excessive size value in Windows Local Security Authority Subsystem Service (LSASS) allows an unauthorized attacker to deny service over a network. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
Sources
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