None of our Mobility products (Acronis Access, ExtremeZ-IP and Masstransit) are vulnerable to ShellShock Bash security bug.
Users with MassTransit on OS X servers should follow Apple's recommendations on securing their OS (this is our general advice, working with Acronis products does not expose your machine to this vulnerability). Apple released patches for OS X 10.7, 10.8 and 10.9 that fix the ShellShock vulnerability: