CVE-2021-21789Public exploit

Local privilege escalation via exposed IOCTL write

Published Jul 7, 2021 · Updated Aug 3, 2024

Privilege escalation in IObit Advanced SystemCare Ultimate 14.2.0.220 allows local users to gain elevated privileges via a malicious IRP. The monitoring driver exposes a world-readable device and accepts IOCTL 0x9c40a0e0, using attacker-supplied dwords as an I/O port and OUT value without sufficient access control. A local low-privilege user can send the crafted request without user interaction, enabling arbitrary privileged hardware I/O and potential compromise of system confidentiality, integrity, and availability.

CVSS severity8.8
High
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Privilege escalation in IObit Advanced SystemCare Ultimate 14.2.0.220 allows local users to gain elevated privileges via a malicious IRP. The monitoring driver exposes a world-readable device and accepts IOCTL 0x9c40a0e0, using attacker-supplied dwords as an I/O port and OUT value without sufficient access control. A local low-privilege user can send the crafted request without user interaction, enabling arbitrary privileged hardware I/O and potential compromise of system confidentiality, integrity, and availability.

The record

CVE
CVE-2021-21789
Published
Jul 7, 2021
Updated
Aug 3, 2024
Vendor
IObit
Product
Advanced SystemCare Ultimate
Classifications
CWE-782, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=IOBit Advanced SystemCare Ultimate 14.2.0.220

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

IObit · Advanced SystemCare Ultimateversion=IOBit Advanced SystemCare Ultimate 14.2.0.220

Published CVSS scores

8.8NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
4.6NVDAV:L/AC:L/Au:N/C:P/I:P/A:P
8.8TalosCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-782Exposed IOCTL with Insufficient Access Control
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo