March 4, 2024 · Applied Cybernetics Group
CVE-2024-21338 — Microsoft Windows
known ransomware use
Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability
- Added to KEV
2024-03-04- Federal due date
2024-03-25- Vendor
- Microsoft
- Product
- Windows
- EPSS
- 99.1th percentile (score 0.598, as of
2026-09-16) - NVD CVSS v3.1
- 7.8 (HIGH)
- Ransomware use
- Known
- Upstream
- https://nvd.nist.gov/vuln/detail/CVE-2024-21338
CISA short description
Microsoft Windows Kernel contains an exposed IOCTL with insufficient access control vulnerability within the IOCTL (input and output control) dispatcher in appid.sys that allows a local attacker to achieve privilege escalation.
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
NVD description
Windows Kernel Elevation of Privilege Vulnerability