[SA13143] RealVNC Multiple Connections Denial of Service Vulnerability

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TITLE:
RealVNC Multiple Connections Denial of Service Vulnerability

SECUNIA ADVISORY ID:
SA13143

VERIFY ADVISORY:
http://secunia.com/advisories/13143/

CRITICAL:
Less critical

IMPACT:
DoS

WHERE:
>From remote

SOFTWARE:
RealVNC 4.x
http://secunia.com/product/3719/

DESCRIPTION:
A vulnerability has been discovered in RealVNC, which can be
exploited by malicious people to cause a DoS (Denial of Service).

The vulnerability is caused due to an error in the connection
handling and can be exploited by establishing around 100 connections
to port 5800/tcp or port 5900/tcp.

Successful exploitation prevents further connections from being
established.

The vulnerability has been confirmed in version 4.0 for Windows.
Other versions may also be affected.

SOLUTION:
Restrict access to the services.

PROVIDED AND/OR DISCOVERED BY:
Originally discovered by:
Allan Zhang

Reported to also affect port 5800/tcp by:
Dr_insane

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