CVE Watch—

CVE-2024-21338

Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability

CVSS

—

No CVSS

EPSS

51.9%

p99

KEV

YES

Mar 4, 2024

Exploit Today

0-100

Published: — · Last modified: —

EPSS · 30d

51.9%EPSS · 30 days51.9%

2026-06-302026-07-16

KEV catalog record

Product

Microsoft / Windows

Vulnerability

Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control Vulnerability

Added to KEV

Mar 4, 2024

Remediate by

Mar 25, 2024

Known ransomware use

Yes

Summary 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.

Notes

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21338; https://nvd.nist.gov/vuln/detail/CVE-2024-21338

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