Cyber Resilience

CVE-2021-21788

HighPublic PoC

Published: 07 July 2021

Published
07 July 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0005 16.1th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21788 is a high-severity Exposed IOCTL with Insufficient Access Control (CWE-782) vulnerability in Iobit Advanced Systemcare Ultimate. Its CVSS base score is 8.8 (High).

Operationally, ranked at the 16.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

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 0x9c40a0dc, the first dword passed in the input buffer is the device port to write to and the word…

more

at offset 4 is the value to write via the OUT instruction. The OUT instruction can write one byte to the given I/O device port, potentially leading to escalated privileges of unprivileged users. A local attacker can send a malicious IRP to trigger this vulnerability.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

iobit
advanced systemcare ultimate
14.2.0.220

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References