CVE-2021-42979

Name: CVE-2021-42979
Creator: NVD / NIST
Published: 2021-12-07T20:15:07.53+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.48%

Last modified Jun 17, 2026

CVE-2021-42979 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. NoMachine Cloud Server is affected by Integer Overflow. IOCTL Handler 0x22001B in the NoMachine Cloud Server above 4.0.346 and below 7.7.4 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.. EPSS estimates a 0.48% chance of exploitation in the next 30 days.

Description

NoMachine Cloud Server is affected by Integer Overflow. IOCTL Handler 0x22001B in the NoMachine Cloud Server above 4.0.346 and below 7.7.4 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.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS Probability

0.48%

37.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-190

Affected Software

Vendor	Product	Versions
Nomachine	Cloud Server	> 4.0.346, < 7.7.4

References

https://www.sentinelone.com/labs/usb-over-ethernet-multiple-privilege-escalation-vulnerabilities-in-aws-and-other-major-cloud-services/Exploit, Technical Description, Third Party Advisory
https://www.sentinelone.com/labs/usb-over-ethernet-multiple-privilege-escalation-vulnerabilities-in-aws-and-other-major-cloud-services/Exploit, Technical Description, Third Party Advisory

Timeline

Published: Dec 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-42979?

How severe is CVE-2021-42979?

CVE-2021-42979 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.48% probability of exploitation in the next 30 days.

How do I fix CVE-2021-42979?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-42979?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST