Security Tips

Most people use passwords that are based on personal information and are easy to remember. However, that also makes it easier for an attacker to guess or "crack" them. Consider a four-digit PIN number. Is yours a combination of the month, day, or year of your birthday? Or the last four digits of your social security number? Or your address or phone number? Think about how easily it is to find this information out about somebody. What about your email password—is it a word that can be found in the dictionary? If so, it may be susceptible to "dictionary" attacks, which attempt to guess passwords based on words in the dictionary.

Although intentionally misspelling a word ("daytt" instead of "date") may offer some protection against dictionary attacks, an even better method is to rely on a series of words and use memory techniques, or mnemonics, to help you remember how to decode it. For example, instead of the password "hoops," use "IlTpbb" for "[I] [l]ike [T]o [p]lay [b]asket[b]all." Using both lowercase and capital letters adds another layer of obscurity. Your best defense, though, is to use a combination of numbers, special characters, and both lowercase and capital letters. Change the same example we used above to "Il!2pBb." and see how much more complicated it has become just by adding numbers and special characters.

Longer passwords are more secure than shorter ones because there are more characters to guess, so consider using passphrases when you can. For example, "This passwd is 4 my email!" would be a strong password because it has many characters and includes lowercase and capital letters, numbers, and special characters. You may need to try different variations of a passphrase—many applications limit the length of passwords, and some do not accept spaces. Avoid common phrases, famous quotations, and song lyrics.

Don't assume that now that you've developed a strong password you should use it for every system or program you log into. If an attacker does guess it, he would have access to all of your accounts. You should use these techniques to develop unique passwords for each of your accounts.

Here is a review of tactics to use when choosing a password:

1. Don't use passwords that are based on personal information that can be easily accessed or guessed.
2. Don't use words that can be found in any dictionary of any language.
3. Develop a mnemonic for remembering complex passwords.
4. Use both lowercase and capital letters.
5. Use a combination of letters, numbers, and special characters.
6. Use passphrases when you can.
7. Use different passwords on different systems.

Now that you've chosen a password that's difficult to guess, you have to make sure not to leave it someplace for people to find. Writing it down and leaving it in your desk, next to your computer, or, worse, taped to your computer, is just making it easy for someone who has physical access to your office. Don't tell anyone your passwords, and watch for attackers trying to trick you through phone calls or email messages requesting that you reveal your passwords (see Avoiding Social Engineering and Phishing Attacks) for more information.

If your Internet service provider (ISP) offers choices of authentication systems, look for ones that use Kerberos, challenge/response, or public key encryption rather than simple passwords (see Understanding ISPs and Supplementing Passwords for more information). Consider challenging service providers that only use passwords to adopt more secure methods.

Also, many programs offer the option of "remembering" your password, but these programs have varying degrees of security protecting that information. Some programs, such as email clients, store the information in clear text in a file on your computer. This means that anyone with access to your computer can discover all of your passwords and can gain access to your information. For this reason, always remember to log out when you are using a public computer (at the library, an Internet cafe, or even a shared computer at your office). Other programs, such as Apple's Keychain and Palm's Secure Desktop, use strong encryption to protect the information. These types of programs may be viable options for managing your passwords if you find you have too many to remember.

There's no guarantee that these techniques will prevent an attacker from learning your password, but they will make it more difficult.

There are steps you can take to protect the data on your USB drive and on any computer that you might plug the drive into:

Take advantage of security features - Use passwords and encryption on your USB drive to protect your data, and make sure that you have the information backed up in case your drive is lost (see Protecting Portable Devices: Data Security for more information).

Keep personal and business USB drives separate - Do not use personal USB drives on computers owned by your organization, and do not plug USB drives containing corporate information into your personal computer.

Use and maintain security software, and keep all software up to date - Use a firewall, anti-virus software, and anti-spyware software to make your computer less vulnerable to attacks, and make sure to keep the virus definitions current (see Understanding Firewalls, Understanding Anti-Virus Software, and Recognizing and Avoiding Spyware for more information). Also, keep the software on your computer up to date by applying any necessary patches (see Understanding Patches for more information).

Do not plug an unknown USB drive into your computer - If you find a USB drive, give it to the appropriate authorities (a location's security personnel, your organization's IT department, etc.). Do not plug it into your computer to view the contents or to try to identify the owner.

Disable Autorun - The Autorun feature causes removable media such as CDs, DVDs, and USB drives to open automatically when they are inserted into a drive. By disabling Autorun, you can prevent malicious code on an infected USB drive from opening automatically. In How to disable the Autorun functionality in Windows, Microsoft has provided a wizard to disable Autorun. In the "More Information" section, look for the Microsoft® Fix it icon under the heading "How to disable or enable all Autorun features in Windows 7 and other operating systems."

Produced 2008, 2011 by US-CERT, a government organization

Social networking sites rely on connections and communication, so they encourage you to provide a certain amount of personal information. When deciding how much information to reveal, people may not exercise the same amount of caution as they would when meeting someone in person because the Internet provides a sense of anonymity the lack of physical interaction provides a false sense of security they tailor the information for their friends to read, forgetting that others may see it they want to offer insights to impress potential friends or associates

While the majority of people using these sites do not pose a threat, malicious people may be drawn to them because of the accessibility and amount of personal information that's available. The more information malicious people have about you, the easier it is for them to take advantage of you. Predators may form relationships online and then convince unsuspecting individuals to meet them in person. That could lead to a dangerous situation. The personal information can also be used to conduct a social engineering attack (see Avoiding Social Engineering and Phishing Attacks for more information). Using information that you provide about your location, hobbies, interests, and friends, a malicious person could impersonate a trusted friend or convince you that they have the authority to access other personal or financial data.

Additionally, because of the popularity of these sites, attackers may use them to distribute malicious code. Sites that offer applications developed by third parties are particularly susceptible. Attackers may be able to create customized applications that appear to be innocent while infecting your computer or sharing your information without your knowledge.

Limit the amount of personal information you post - Do not post information that would make you vulnerable, such as your address or information about your schedule or routine. If your connections post information about you, make sure the combined information is not more than you would be comfortable with strangers knowing. Also be considerate when posting information, including photos, about your connections.

Remember that the Internet is a public resource - Only post information you are comfortable with anyone seeing. This includes information and photos in your profile and in blogs and other forums. Also, once you post information online, you can't retract it. Even if you remove the information from a site, saved or cached versions may still exist on other people's machines (see Guidelines for Publishing Information Online for more information).

Be wary of strangers - The Internet makes it easy for people to misrepresent their identities and motives (see Using Instant Messaging and Chat Rooms Safely for more information). Consider limiting the people who are allowed to contact you on these sites. If you interact with people you do not know, be cautious about the amount of information you reveal or agreeing to meet them in person.

Be sceptical - Don't believe everything you read online. People may post false or misleading information about various topics, including their own identities. This is not necessarily done with malicious intent; it could be unintentional, an exaggeration, or a joke. Take appropriate precautions, though, and try to verify the authenticity of any information before taking any action.

Evaluate your settings - Take advantage of a site's privacy settings. The default settings for some sites may allow anyone to see your profile, but you can customize your settings to restrict access to only certain people. There is still a risk that private information could be exposed despite these restrictions, so don't post anything that you wouldn't want the public to see. Sites may change their options periodically, so review your security and privacy settings regularly to make sure that your choices are still appropriate.

- Be wary of third-party applications - third-party applications may provide entertainment or functionality, but use caution when deciding which applications to enable. Avoid applications that seem suspicious, and modify your settings to limit the amount of information the applications can access.

Use strong passwords - Protect your account with passwords that cannot easily be guessed (see Choosing and Protecting Passwords for more information). If your password is compromised, someone else may be able to access your account and pretend to be you.

Check privacy policies - Some sites may share information such as email addresses or user preferences with other companies. This may lead to an increase in spam (see Reducing Spam for more information). Also, try to locate the policy for handling referrals to make sure that you do not unintentionally sign your friends up for spam. Some sites will continue to send email messages to anyone you refer until they join.

Keep software, particularly your web browser, up to date - Install software updates so that attackers cannot take advantage of known problems or vulnerabilities (see Understanding Patches for more information). Many operating systems offer automatic updates. If this option is available, you should enable it.

Use and maintain anti-virus software - Anti-virus software helps protect your computer against known viruses, so you may be able to detect and remove the virus before it can do any damage (see Understanding Anti-Virus Software for more information). Because attackers are continually writing new viruses, it is important to keep your definitions up to date.

Children are especially susceptible to the threats that social networking sites present. Although many of these sites have age restrictions, children may misrepresent their ages so that they can join. By teaching children about Internet safety, being aware of their online habits, and guiding them to appropriate sites, parents can make sure that the children become safe and responsible users (see Keeping Children Safe Online for more information).