Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2021-42973

26
FAUCET Score

CVE-2021-42973 describes an integer overflow vulnerability in NoMachine Server versions above 4.0.346 and below 7.7.4. This flaw, residing in IOCTL Handler 0x22001B, allows a local attacker to achieve arbitrary code execution in kernel mode or trigger a denial of service through memory corruption and OS crash using a specially crafted I/O Request Packet. With a CVSS score of 8.8 (HIGH), the vulnerability has a low attack complexity and requires local privileges, but can lead to high impact on confidentiality, integrity, and availability. While there is no evidence of active exploitation or public exploit code (Metasploit, Nuclei, ExploitDB), it has garnered some community discussion and media coverage, indicating awareness within the cybersecurity community.

Impacted Technologies

VendorProductVersion(s)CPE
> 4.0.346, < 7.7.4CPE matchmatch criteria
cpe:2.3:a:nomachine:server:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

8.8HIGH

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

Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
2.0
Impact Score
6.0
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.48%
Probability of exploitation in next 30 days
EPSS Percentile
38.8%
Percentile rank of EPSS score among Peer Group
As of 2026-07-25
Model: v2026.06.15
This CVE's current EPSS score of 0.0048 is in the 79th percentile among its peer group of 16,994 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.2 Bluesky, 0.1 Mastodon, and 0.2 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

sentinelone.com / labs/usb-over-ethernet-multiple-privilege-escalation-vulnerabilities-in-aws-and-other-major-cloud-services
ExploitTechnical DescriptionThird Party Advisory