CVE-2021-21788
mediumpriority · track · 35EPSS 0.003 · 25 %ileEUUSEPSS · scored 2026-10-26
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.6–8.8
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
- iobit advanced systemcare ultimate= 14.2.0.220nvdUScpe:2.3:a:iobit:advanced_systemcare_ultimate:*:*:*:*:*:*:*:*
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021070808cnnvd
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254enisa_euvd
- https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254ExploitThird Party Advisorynvd
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