What is CVE-2021-42993?

CVE-2021-42993 is a high-severity vulnerability in Flexihub, classified under Integer Overflow or Wraparound. CVSS score: 8.8/10. Published 2021-12-07.

How severe is CVE-2021-42993?

High severity. CVSS v3 base score is 8.8 out of 10.

Integer overflow in Flexihub

CVE-2021-42993

FlexiHub For Windows is affected by Integer Overflow. IOCTL Handler 0x22001B in the FlexiHub For Windows above 2.0.4340 below 5.3.14268 allow local attackers to execute arbitrary code in kernel mode or cause a denial of service (memory corruption and OS crash) via specially crafted I/O Request Packet.

Vulnerability class: Integer Overflow

Published 2021-12-07 · last modified 2026-06-17.

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: 0.005 (38.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

www.sentinelone.com/labs/usb-over-ethernet-multiple-privilege-escalation-vulner… (Technical Description, Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2021-42993?: CVE-2021-42993 is a high-severity vulnerability in Flexihub, classified under Integer Overflow or Wraparound. CVSS score: 8.8/10. Published 2021-12-07.
How severe is CVE-2021-42993?: High severity. CVSS v3 base score is 8.8 out of 10.