CVE-2021-21789

HighCVSS 8.8/10Last modified Jun 17, 2026

Description

A privilege escalation vulnerability exists in the way IOBit Advanced SystemCare Ultimate 14.2.0.220 driver handles Privileged I/O write requests. During IOCTL 0x9c40a0e0, the first dword passed in the input buffer is the device port to write to and the dword at offset 4 is the value to write via the OUT instruction. A local attacker can send a malicious IRP to trigger this vulnerability.

Metrics

CVSS 3.1 8.8/10CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weakness enumeration

CWE-782

Affected software

Vendor	Product	Versions
n/a	Iobit	IOBit Advanced SystemCare Ultimate 14.2.0.220

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254Exploit, Third Party Advisory
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254Exploit, Third Party Advisory

Timeline

Published: Jul 7, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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