Vulnerability in Iobit Advanced Systemcare Ultimate

CVE-2021-21788

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 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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (22.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 23rd percentile — 22.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-21788: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-21788?
CVE-2021-21788 is a high-severity vulnerability in Iobit Advanced Systemcare Ultimate, classified under CWE-782. CVSS score: 8.8/10. Published 2021-07-07.
How severe is CVE-2021-21788?
High severity. CVSS v3 base score is 8.8 out of 10.