Every business, including yours, has valuable IT assets such as computers, networks, and data. And protecting those assets, requires that companies big and small conduct their own IT security audits in order to get a clear picture of the security risks they face and how to best deal with those threats.
The following are 10 steps to conducting your own basic IT security audit. While these steps won't be as extensive as audits provided by professional consultants, this DIY version will get you started on the road to protecting your own company.
1. DEFINING THE SCOPE OF YOUR AUDIT: CREATING ASSET LISTS AND A SECURITY PERIMETERThe first step in conducting an audit is to create a master list of the assets your company has, in order to later decide upon what needs to be protected through the audit. While it is easy to list your tangible assets, things like computers, servers, and files, it becomes more difficult to list intangible assets. To ensure consistency in deciding which intangible company assets are included, it is helpful to draw a "security perimeter" for your audit.
What is the Security Perimeter?
The security perimeter is both a conceptual and physical boundary within which your security audit will focus, and outside of which your audit will ignore. You ultimately decide for yourself what your security perimeter is, but a general rule of thumb is that the security perimeter should be the smallestboundary that contains the assets that you own and/or need to control for your own company's security.
Assets to Consider
Once you have drawn up your security perimeter, it is time to complete your asset list. That involves considering every potential company asset and deciding whether or not it fits within the "security perimeter" you have drawn. To get you started, here is a list of common sensitive assets:
- Computers and laptops
- Routers and networking equipment
- Cameras, digital or analog, with company-sensitive photographs
- Data - sales, customer information, employee information
- Company smartphones/ PDAs
- VoIP phones, IP PBXs (digital version of phone exchange boxes), related servers
- VoIP or regular phone call recordings and records
- Log of employees daily schedule and activities
- Web pages, especially those that ask for customer details and those that are backed by web scripts that query a database
- Web server computer
- Security cameras
- Employee access cards.
- Access points (i.e., any scanners that control room entry)
2. CREATING A 'THREATS LIST'You can't protect assets simply by knowing what they are, you also have to understand how each individual asset is threatened. So in this stage you will compile an overall list of threats which currently face your assets.
What Threats to Include?
If your threat list is too broad, your security audit will end up getting focused on threats which are extremely small or remote. When deciding whether to include a particular threat on your 'Threat List' keep in mind that your test should follow a sliding scale. For example, if you are considering whether the possibility of a hurricane flooding out your servers you should consider both, how remote the threat is, but also how devastating the harm would be if it occurred. A moderately remote harm can still be reasonably included in your threat list if the potential harm it would bring is large enough to your company.
Common 'Threats' to Get you Started?
Here are some relatively common security threats to help you get started in creating your company's threat list:
- Computer and network passwords. Is there a log of all people with passwords (and what type). How secure is this ACL list, and how strong are the passwords currently in use?
- Physical assets. Can computers or laptops be picked up and removed from the premises by visitors or even employees?
- Records of physical assets. Do they exist? Are they backed up?
- Data backups. What backups of virtual assets exist, how are they backed up, where are the backups kept, and who conducts the backups?
- Logging of data access. Each time someone accesses some data, is this logged, along with who, what, when, where, etc.?
- Access to sensitive customer data, e.g., credit card info. Who has access? How can access be controlled? Can this information be accessed from outside the company premises?
- Access to client lists. Does the website allow backdoor access into the client database? Can it be hacked?
- Long-distance calling. Are long-distance calls restricted, or is it a free-for-all? Should it be restricted?
- Emails. Are spam filters in place? Do employees need to be educated on how to spot potential spam and phishing emails? Is there a company policy that outgoing emails to clients not have certain types of hyperlinks in them?
3. PAST DUE DILIGENCE & PREDICTING THE FUTUREAt this point, you have compiled a list of current threats, but what about security threats that have not come on to your radar yet, or haven't even been developed? A good security audit should account not just for those security threats that face your company today, but those that will arise in the future.
Examining Your Threat History
The first step towards predicting future threats is to examine your company's records and speak with long-time employees about past security threats that the company has faced. Most threats repeat themselves, so by cataloging your company's past experiences and including the relevant threats on your threat list you'll get a more complete picture of your company's vulnerabilities.
Checking Security Trends
In addition to checking for security threats specific to your particular industry,ITSecurity.com's recent white paper covers trends for 2007 as well as offering a regularly updated blog which will keep you abreast of all new security threat developments. Spend some time looking through these resources and consider how these trends are likely to affect your business in particular. If you're stumped you may want to Ask the IT Security Experts directly.
Checking with your Competition
When it comes to outside security threats, companies that are ordinarily rivals often turn into one another's greatest asset. By developing a relationship with your competition you can develop a clearer picture of the future threats your company will face by sharing information about security threats with one another.
4. PRIORITIZING YOUR ASSETS & VULNERABILITIESYou have now developed a complete list of all the assets and security threats that your company faces. But not every asset or threat has the same priority level. In this step, you will prioritize your assets and vulnerabilities in order to know your company's greatest security risks, and so that you can allocate your company's resources accordingly.
Perform a Risk Calculation/ Probability Calculation
The bigger the risk, the higher priority dealing with the underlying threat is. The formula for calculating risk is:
Risk = Probability x Harm
The risk formula just means that you multiply the likelihood of a security threat actually occurring (probability) times the damage that would occur to your company if the threat actually did occur (harm). The number that comes out of that equation, is the risk that threat poses to your company.
Probability is simply the chance that a particular threat will actually occur. Unfortunately, there isn't a book that lists the probability that your website will be hacked this year, so you have to come up with those figures yourself.
Your first step in calculating probability should be to do some research into your company's history with this threat, your competitors' history, and any empirical studies on how often most companies face this threat. Any probability figure that you ultimately come up with is an estimate, but the more accurate the estimate, the better your risk calculation will be.
How much damage would a particular threat cause if it occurred? Calculating the potential harm of a threat can be done in a number of different ways. You might count up the cost in dollars that replacing the lost revenue or asset would cost the company. Or instead you might calculate the harm as the number of man-hours which would be lost trying to remedy the damage once it has occurred. But whatever method you use, it is important that you stay consistent throughout the audit in order to get an accurate priorities list.
DEVELOPING YOUR SECURITY THREAT RESPONSE PLANWhen working down your newly developed priority list, there will be a number of potential responses you could make to any particular threat. The remaining six points in this article cover the primary responses a company can make to a particular threat. While these security responses are by no means the only appropriate ways to deal with a security threat, they will cover the vast majority of the threats your company faces, and as a result you should go through this list of potential responses before considering any alternatives.
5. IMPLEMENTING NETWORK ACCESS CONTROLSNetwork Access Controls, or NACs, check the security of any user trying to access a network. So, for example, if you are trying to come up with a solution for the security threat of your competition stealing company information from private parts of the company's website, applying network access controls or NACs is an excellent solution.
Part of implementing effective NAC is to have an ACL (Access Control List), which indicates user permissions to various assets and resources. Your NAC might also include steps such as; encryption, digital signatures, ACLs, verifying IP addresses, user names, and checking cookies for web pages.
6. IMPLEMENTING INTRUSION PREVENTION
While a Network Access Control deals with threats of unauthorized people accessing the network by taking steps like password protecting sensitive data, an Intrustion Prevention System (IPS) prevents more malicious attacks from the likes of hackers.
The most common form of an IPS is a second generation firewall. Unlike first generation firewalls, which were merely content based filters, a second generation firewall adds to the content filter a 'Rate-based filter'.
7. IMPLEMENTING IDENTITY & ACCESS MANAGEMENTIdentity and Access Management (IAM) simply means controlling users' access to specific assets. Under an IAM, users have to manually or automatically identify themselves and be authenticated. Once authenticated, they are given access to those assets to which they are authorized.
An IAM is a good solution when trying to keep employees from accessing information they are not authorized to access. So, for instance, if the threat is that employees will steal customers credit card information, an IAM solution is your best bet.
8. CREATING BACKUPSWhen we think of IT security threats, the first thing that comes to mind is hacking. But a far more common threat to most companies is the accidental loss of information. Although it's not sexy, the most common way to deal with threats of information loss is to develop a plan for regular backups. These are a few of the most common backup options and questions you should consider when developing your own backup plan:
9. EMAIL PROTECTION & FILTERING
Each day, 55 billion spam messages are sent by email throughout the world. To limit the security risk that unwanted emails pose, spam filters and an educated workforce are a necessary part of every company's security efforts. So, if the threat you are confronting is spam emails, the obvious (and correct) response is to implement an email security and filtering system for your company.
While the specific email security threats confronting your company will determine the appropriate email protections you choose, here are a few common features:
10. PREVENTING PHYSICAL INTRUSIONSDespite the rise of new generation threats like hacking and email spam, old threats still imperil company assets. One of the most common threats is physical intrusions. If, for example, you are trying to deal with the threat of a person breaking into the office and stealing company laptops, and along with them valuable company information, then a plan for dealing with physical intrusions is necessary.
Here are some common physical threats along with appropriate solutions for dealing with them:
These 10 steps to conducting your own IT Security Audit will take you a long way towards becoming more aware of the security threats facing your company as well as help you begin to develop a plan for confronting those threats. But it is important to remember that security threats are always changing, and keeping your company safe will require that you continually assess new threats and revisit your response to old ones.
For further research, visit IT Security's Security Audit Resource Center.