Executive Summary

Title UltraVNC buffer overflow vulnerability
Name VU#721460 First vendor Publication 2008-03-15
Vendor VU-CERT Last vendor Modification 2008-03-16
Severity (Vendor) N/A Revision M

Security-Database Scoring CVSS v3

Cvss vector : N/A
Overall CVSS Score NA
Base Score NA Environmental Score NA
impact SubScore NA Temporal Score NA
Exploitabality Sub Score NA
Calculate full CVSS 3.0 Vectors scores

Security-Database Scoring CVSS v2

Cvss vector : (AV:N/AC:M/Au:N/C:C/I:C/A:C)
Cvss Base Score 9.3 Attack Range Network
Cvss Impact Score 10 Attack Complexity Medium
Cvss Expoit Score 8.6 Authentication None Required
Calculate full CVSS 2.0 Vectors scores


Vulnerability Note VU#721460

UltraVNC buffer overflow vulnerability


UltraVNC viewer contains a buffer overflow vulnerability. If exploited, this vulnerability may allow an attacker to execute arbitrary code.

I. Description

UltraVNC viewer is a remote desktop application that allows a user to control compatible VNC servers. The UltraVNC viewer includes a listen mode that accepts connections from remote hosts.

The UltraVNC viewer contains a buffer overflow vulnerability. This vulnerability may be triggered by sending a malformed packet during the protocol negotiation phase of a VNC session.

II. Impact

A remote, unauthenticated attacker may be able to execute arbitrary code.

III. Solution


See the UltraVNC download page for information about obtaining fixed software.

Data Stream Encryption Plugin

Using the Data Stream Encryption (DSM) plugin will prevent this vulnerability from being exploited by attackers who do not have access to the encryption key material.

Restrict access

Restricting access to a vulnerable system by using host or network based firewalls may prevent a remote attacker from exploiting this vulnerability. Microsoft Windows XP users should see the Technet articleHow to Configure Windows Firewall on a Single Computer and Windows Vista and Server 2008 users should refer to the Vista Technet article Getting Started with Windows Firewall with Advanced Security in Windows Vista and Windows Server 2008 for more information about configuring the Windows Firewall. Note that UltraVNC runs on ports 5500/tcp and 5400/tcp by default.

Systems Affected

VendorStatusDate Updated




Thanks to the UltraVNC team and Secunia for information that was used in this report.

This document was written by Ryan Giobbi.

Other Information

Date Public02/01/2008
Date First Published03/15/2008 11:44:06 AM
Date Last Updated03/16/2008
CERT Advisory 
CVE NameCVE-2008-0610
US-CERT Technical Alerts 
Document Revision31

Original Source

Url : http://www.kb.cert.org/vuls/id/721460

CWE : Common Weakness Enumeration

% Id Name
100 % CWE-119 Failure to Constrain Operations within the Bounds of a Memory Buffer

CPE : Common Platform Enumeration

Application 5

Open Source Vulnerability Database (OSVDB)

Id Description
42840 UltraVNC vncviewer/ClientConnection.cpp ClientConnection::NegotiateProtocolVe...

Snort® IPS/IDS

Date Description
2014-01-10 UltraVNC Listening mode stack buffer overflow attempt
RuleID : 26455 - Revision : 3 - Type : SERVER-OTHER
2014-01-10 UltraVNC Listening mode stack buffer overflow attempt
RuleID : 26454 - Revision : 3 - Type : SERVER-OTHER