CVE-2026-40397
Windows Common Log File System Driver Elevation of Privilege vulnerability
MSRC advisory May 12, 2026
Alert details
- Source feed
- Microsoft MSRC
- CVE ID
- CVE-2026-40397
- Affected products
- Windows Common Log File System Driver Elevation of Privilege · Microsoft Windows Common Log File System Driver Elevation of Privilege · Microsoft
What happened
Integer underflow (wrap or wraparound) in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally.
What it means for your business
Windows Common Log File System Driver Elevation of Privilege vulnerability (CVE-2026-40397) was added to Microsoft’s security update guidance. Integer underflow (wrap or wraparound) in Windows Common Log File System Driver allows an authorized attacker to elevate privileges locally. PremierePC tracks MSRC advisories for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
EPSS probability
0.27%
Sources
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Need help patching?
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