But what happens when the whitelist, itself, becomes compromised? That’s the scenario that’s playing out with customers of whitelisting firm Bit9, which acknowledged a breach of its corporate network that allowed unknown assailants to gain control of an application code signing server. (https://blog.bit9.com/2013/02/08/bit9-and-our-customers-security/) The incident began with compromises of machines on Bit9's network that were not running Bit9's software — something that Bit9 encourages its own customers not to do. The company's acknowledgement came after Bit9 was contacted regarding the breach by Brian Krebs of Krebsonsecurity.com, which broke the news Friday. (http://krebsonsecurity.com/2013/02/security-firm-bit9-hacked-used-to-spread-malware/)"
Link to Original Source