CVE-2020-37134

UltraVNC Viewer 1.2.4.0 contains a denial of service vulnerability that allows attackers to crash the application by manipulating VNC Server input. Attackers can generate a malformed 256-byte payload and paste it into the VNC Server connection dialog to trigger an application crash.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.exploit-db.com/exploits/48291
https://www.uvnc.com/
https://www.vulncheck.com/advisories/ultravnc-viewer-vncserver-denial-of-service

Configurations

No configuration.

History

15 Apr 2026, 00:35

Type	Values Removed	Values Added
Summary		(es) UltraVNC Viewer 1.2.4.0 contiene una vulnerabilidad de denegación de servicio que permite a los atacantes bloquear la aplicación manipulando la entrada del servidor VNC. Los atacantes pueden generar una carga útil malformada de 256 bytes y pegarla en el diálogo de conexión del servidor VNC para provocar un bloqueo de la aplicación.

05 Feb 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-05 17:16

Updated : 2026-04-15 00:35

NVD link : CVE-2020-37134

Mitre link : CVE-2020-37134

CVE.ORG link : CVE-2020-37134

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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