Buffer overflow in Nomachine

CVE-2026-114549

NoMachine nxwebrunner Heap-based Buffer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of NoMachine. Authentication is not required to exploit this vulnerability. The specific flaw exists within the web service, which listens on TCP port 4443 by default. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a heap-based buffer. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-30685.

Vulnerability class: Buffer Overflow

Published .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-114549?
CVE-2026-114549 is a critical-severity vulnerability in Nomachine, classified under Heap-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-11-04.
How severe is CVE-2026-114549?
Critical severity. CVSS v3 base score is 9.8 out of 10.