30 Minutes to Full Compromise
In our experience, a breach can go from initial entry to full compromise in just a half hour. “Full compromise” means that you cannot get the hackers out without taking extreme measures like taking your system offline or wiping everything. From there, hackers can exfiltrate data undetected within one to three hours.
None of the security solutions offered by vendors these days will magically protect you from being hacked.
As of this writing, we have always found a way to penetrate systems even if they have strongest firewalls, antivirus and anti-malware solutions. They simply cannot withstand targeted attack from a dedicated attacker.
http://www.cmswire.com/information-management/what-hackers-know-about-your-security-that-you-dont/