PT-2021-23703 · Nomachine · Nomachine Server

Kasif Dekel · Published 2021-12-07 · Updated 2021-12-08 · CVE-2021-42973

Positive Technologies (AI Summary)

CVSS v3.1

8.8

High

Base vector

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

Name of the Vulnerable Software and Affected Versions NoMachine Server versions 4.0.347 through 7.7.3

Description The issue is related to an Integer Overflow in the NoMachine Server. Specifically, the IOCTL Handler 0x22001B is vulnerable, allowing local attackers to execute arbitrary code in kernel mode or cause a denial of service, resulting in memory corruption and OS crash, via specially crafted I/O Request Packets.

Recommendations For versions 4.0.347 through 7.7.3, update to version 7.7.4 or later to resolve the issue. As a temporary workaround, consider restricting access to the IOCTL Handler 0x22001B to minimize the risk of exploitation.

Exploit

Fix

Integer Overflow

Weakness Enumeration

CWE-190

Related Identifiers

CVE-2021-42973

Affected Products

Nomachine Server

References · 4

• 🔥 https://sentinelone.com/labs/usb-over-ethernet-multiple-privilege-escalation-vulnerabilities-in-aws-and-other-major-cloud-services · Exploit
• https://osv.dev/vulnerability/CVE-2021-42973 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-42973 · Security Note
• https://t.me/cibsecurity/33512 · Telegram Post