TI-2026-84863 Aliases CVE-2026-114549 GHSA-5x33-389c-c5hr

Heap overflow in NoMachine web service allows remote code execution

MEDIUM 50CWE-122Published 2026-11-03 · Updated 2026-11-06

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.0 · CNA. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

Summary

NoMachine versions from 9.7.3 are affected by a heap-based buffer overflow in the nxwebrunner web service. The service does not validate the length of user-supplied data before copying it to a heap buffer (CWE-122). An unauthenticated remote attacker can execute code in the context of the service account.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Description from the CNA

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00584 48th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
NoMachine	NoMachine	9.7.3	—	No fix listed	CNA

NoMachine VendorNoMachine Affected 9.7.3 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:nomachine:nomachine::::::::	—	—	NoMachine

cpe:2.3:a:nomachine:nomachine:*:*:*:*:*:*:*:* Versions — — ·NoMachine

Remediation

The sources list no fixed version for NoMachine.

Written with Claude Haiku 5.5 from the sources below · 2026-11-04

Timeline

2026-11-03 Threatist record created from CVE-2026-114549
2026-11-04 Alias added: GHSA-5x33-389c-c5hr
2026-11-06 CISA SSVC decision points changed

References

Other 1

ZDI-26-786

TI-2023-20294 An arbitrary file overwrite vulnerability in NoMachine Free Edition and Enterprise Client… CVSS 3.1CRITICAL 9.1
TI-2018-00619 Improper input validation in NoMachine App for Android CVSS 3.0CRITICAL 9.8
TI-2017-09455 An unspecified server utility in NoMachine before 5.3.10 on Mac OS X and Linux allows… CVSS 3.0HIGH 8.8
TI-2026-15017 OS command injection in NoMachine CVSS 3.0HIGH 8.8
TI-2026-78898 Heap overflow in NoMachine mDNS parsing enables remote code execution CVSS 3.0HIGH 8.8
TI-2018-12800 NoMachine before 5.3.27 and 6.x before 6.3.6 allows attackers to gain privileges via a… CVSS 3.0HIGH 7.8

See all 31 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences