CVE-2021-21789 json
A privilege escalation vulnerability exists in the way IOBit Advanced SystemCare Ultimate 14.2.0.220 driver handles Privileged I/O write re…
published 2021-07-07 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-8961
- cvss
- 8.8
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 25%
- public exploits
- 0
- none known
Summary
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.
Exploit prediction
0.32% chance of exploitation in the next 30 days, higher than 25% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- talosintelligence.com https://talosintelligence.com/vulnerability_reports/TALOS-2021-1254 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 8.8 | CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| NVD | 2.0 | 4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- n/a Iobit
Classification
- Weakness
-
- CWE-782 Exposed IOCTL with Insufficient Access Control
References
-
talosintelligence.com
/vulnerability_reports/TALOS-2021-1254
exploit, third-party-advisory
Sources
- CVE List CVE-2021-21789
- NVD CVE-2021-21789
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