The best security against malware, spam, hacker attacks, policy breaches and other email and web threats is a layered set of defenses in which software, services, hardware and policies are incorporated to safeguard data and other assets at the network, system and application tiers. However, an obvious – but often-disregarded – layer in this cake of protection is the common sense of your staff – one of the critical layers to stop threats from gaining a foothold. As the picture says ‘just because you can, doesn’t mean you should’, this is where common sense is important.

Spear phishing is an increasing issue where a targeted false email that seems to be legitimate is sent to individuals or a company in order to obtain data. For instance e, by looking at a Facebook page of someone with whom I am not connected. I can see that she is a realtor, has listed a home at 657 Noble in [city name withheld], was born on January 26th, has a cat named Lou, is a member of the Agent Leadership Council at a southern California realty organization, likes ice skating, resides in Thousand Oaks, speaks French, and took a vacation to Orlando on February 11th. If I was a hacker intent on sending her a spear phishing email – perhaps with the intent of infecting her PC with Zeus – I could use these details to craft an email that she would be likely to click on. For example, an email with the title “Need to schedule a vet appointment for Lou” or “We mistakenly overcharged you on your recent trip to Orlando”, or maybe even a LinkedIn invitation that includes personal details, would likely get her attention and increase the possibility of her becoming a victim of a spear phisher. This is not to say that this Facebook customer lacks common sense, but the details she has posted could be used against her and her company and needs to be looked at in that light.

Spam filtering technology is successful at preventing spam emails that include links to malware sources (albeit with some spam filters more effective than others). The RSA exploit in April 2011, in which some staff members received an email with an Excel attachment, was due to spear phishing emails that were effectively quarantined by spam filtering technology, but later opened by staff members from the quarantine. A spear phishing email at the Oak Ridge National Laboratory in April 2011 was received by 530 workers, 11% of whom clicked on a malicious link. Many users are not adequately when asked for information. For instance, before last year’s royal wedding between Prince William and Kate Middleton, a Facebook hacking scam was doing the rounds asking respondents to create their royal wedding guest name. This name consisted of one grandparent’s name, the name of a first pet, and the name of the street on which the victim lived when they were younger – all likely responses to security questions one might get asked when resetting a password.