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features, which makes it even easier to stay patched.

Download and test it today:
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TITLE:
UltraVNC vncviewer Multiple Buffer Overflow Vulnerabilities

SECUNIA ADVISORY ID:
SA28804

VERIFY ADVISORY:
http://secunia.com/advisories/28804/

CRITICAL:
Highly critical

IMPACT:
System access

WHERE:
>From remote

SOFTWARE:
UltraVNC (formerly Ultr@VNC) 1.x
http://secunia.com/product/2836/

DESCRIPTION:
Some vulnerabilities have been reported in UltraVNC, which can
potentially be exploited by malicious people to compromise a user's
system.

The vulnerabilities are caused due to multiple boundary errors within
the vncviewer/FileTransfer.cpp file. These can be exploited to cause
stack-based buffer overflows by e.g. sending specially crafted data
to a vncviewer in "LISTENING" mode or by tricking a user into
connecting to a malicious VNC server.

Successful exploitation may allow execution of arbitrary code.

This may also be exploited if a DSM plugin is used, but requires that
the attacker owns the encryption key used by vncviewer.

The vulnerability is reported in version 102 and in release
candidates of version 1.0.4 prior to February 4th, 2008.

SOLUTION:
Apply updated version.
http://downloads.sourceforge.net/ultravnc/UltraVNC-Viewer-104-Security-Update-2---Feb-8-2008.zip

PROVIDED AND/OR DISCOVERED BY:
Reported by the vendor.

ORIGINAL ADVISORY:
http://forum.ultravnc.info/viewtopic.php?p=45150#45150

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About:
This Advisory was delivered by Secunia as a free service to help
everybody keeping their systems up to date against the latest
vulnerabilities.

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http://secunia.com/about_secunia_advisories/


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