Security Advisory 06 – 044 – The VSAOD server allows remote execution via replay attacks
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.
All known versions of Audit, this vulnerability was discovered for version 220.127.116.11.
In order for the Audit client to schedule an audit it connects to the remote VSAOD server and initiates the following exchange:
server> Visionsoft Audit on Demand Service server> Version: 18.104.22.168 server> client> DETAILS client> [windows domain] client>
User: user ID is incorrectclient> [obscured password] client> OK client> PROCESS client> [path to executable] server> [status message|OK|FAIL message]
The VSAOD server will then switch to the supplied Windows domain account and execute the requested executable. The supplied Windows domain account does not require special privileges, although obviously using a privileged account will allow the executable more access to the remote server. The username and password can be obtained in a number of ways (some of which are vulnerabilities in their own right) including eavesdropping a legitimate session. The requested executable can be either local to the remote server or available via a Microsoft Windows Network share.
An attacker could execute arbitrary code on the server, by passing normal Windows security mechanisms.
Exploit code is not required.
e-mailed – 16th January 2007
e-mailed – 26th February 2007
e-mailed – 15th March 2007