Barracuda Spam Firewall 3.1.10 and earlier does not restrict the domains that white-listed domains can send mail to, which allows members of white-listed domains to use Barracuda as an open mail relay for spam.
preview_email.cgi in Barracuda Spam Firewall (BSF) 3.3.01.001 through 3.3.03.053 allows remote attackers to execute commands via shell metacharacters ("|" pipe symbol) in the file parameter. NOTE: the attack can be extended to arbitrary commands by the presence of CVE-2006-4000.
img.pl in Barracuda Spam Firewall running firmware 3.1.16 and 3.1.17 allows remote attackers to execute arbitrary commands via shell metacharacters in the f parameter.