Tried, Tested and Proven

Security Advisory 06 – 040 – The VSAOD server has input validation flaws which can result in an unauthenticated heap overflow

Vulnerable System:

Visionsoft Audit

Vulnerability discovery and development:

Portcullis Security Testing Services discovered this vulnerability during an application assessment.
Further research was then carried out post assessment.

Credit for Discovery:

Tim Brown – Portcullis Computer Security Ltd.

Affected Systems:

All known versions of Audit, this vulnerability was discovered for version


It is possible to set the log file name on the remote VSAOD server using the following unauthenticated exchange:

client> LOG.[filename]

server> Logfile set to: [filename]

When the file name passed is of sufficient length, the remote VSAOD server will terminate. As the server writes the file to its file prior to crashing, the server will terminate every time it is restarted until the ini file has been fixed.


An attacker could cause a Denial of Service or execute arbitrary code. Since the VSAOD server typically runs as SYSTEM, an attacker who successfully executes arbitrary code will fully compromise the system.


Exploit code is not required.

Vendor Status:


e-mailed – 16th January 2007

e-mailed – 26th February 2007

e-mailed – 15th March 2007


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