Thursday, June 24, 2010

Avoiding Copyright Infringement

Cyber Security Tip ST05-004
Avoiding Copyright Infringement

Although copyright may seem to be a purely legal issue, using unauthorized
files could have security implications. To avoid prosecution and minimize
the risks to your computer, make sure you have permission to use any
copyrighted information, and only download authorized files.

How does copyright infringement apply to the internet?

Copyright infringement occurs when you use or distribute information without
permission from the person or organization that owns the legal rights to the
information. Including an image or cartoon on your website or in a document,
illegally downloading music, and pirating software are all common copyright
violations. While these activities may seem harmless, they could have
serious legal and security implications.

How do you know if you have permission to use something?

If you find something on a website that you would like to use (e.g., a
document, a chart, an application), search for information about permissions
to use, download, redistribute, or reproduce. Most websites have a "terms of
use" page that explains how you are allowed to use information from the site
(see US-CERT's terms of use for an example). You can often find a link to
this page in the site's contact information or privacy policy, or at the
bottom of the page that contains the information you are interested in

There may be restrictions based on the purpose, method, and audience. You
may also have to adhere to specific conditions about how much information
you are allowed to use or how the information is presented and attributed.
If you can't locate the terms of use, or if it seems unclear, contact the
individual or organization that holds the copyright to ask permission.

What consequences could you face?

* Prosecution - When you illegally download, reproduce, or distribute
information, you risk legal action. Penalties may range from warnings
and mandatory removal of all references to costly fines. Depending on
the severity of the crime, jail time may also be a possibility. To
offset their own court costs and the money they feel they lose because
of pirated software, vendors may increase the prices of their products.
* Infection - Attackers could take advantage of sites or networks that
offer unauthorized downloads (music, movies, software, etc.) by
including code into the files that would infect your computer once it
was installed (see Understanding Hidden Threats: Corrupted Software
Files and Understanding Hidden Threats: Rootkits and Botnets for more
information). Because you wouldn't know the source or identity of the
infection (or maybe that it was even there), you might not be able to
easily identify or remove it. Pirated software with hidden Trojan horses
is often advertised as discounted software in spam email messages (see
Why is Cyber Security a Problem? and Reducing Spam for more


* U.S. Copyright Office -
* Copyright on the Internet -

Author: Mindi McDowell

Produced 2005 by US-CERT, a government organization.

Note: This tip was previously published and is being
re-distributed to increase awareness.

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Tuesday, June 22, 2010

Reviewing End-User License Agreements

Cyber Security Tip ST05-005
Reviewing End-User License Agreements

Before accepting an end-user license agreement, make sure you understand and
are comfortable with the terms of the agreement.

What is an end-user license agreement?

An end-user license agreement (EULA) is a contract between you and the
software's vendor or developer. Some software packages state that by simply
removing the shrink-wrap on the package, you agree to the contract. However,
you may be more familiar with the type of EULA that is presented as a dialog
box that appears the first time you open the software. It usually requires
you to accept the conditions of the contract before you can proceed.
Software updates and patches may also include new or updated EULAs that have
different terms than the original. Some EULAs only apply to certain features
of the software, so you may only encounter them when you attempt to use
those features.

Unfortunately, many users don't read EULAs before accepting them. The terms
of each contract differ, and you may be agreeing to conditions that you
later consider unfair or that expose you to security risks you didn't

What terms may be included?

EULAs are legal contracts, and the vendor or developer may include almost
any conditions. These conditions are often designed to protect the developer
or vendor against liability, but they may also include additional terms that
give the vendor some control over your computer. The following topics are
often covered in EULAs:
* Distribution - There are often limitations placed on the number of times
you are allowed to install the software and restrictions about
reproducing the software for distribution (see Avoiding Copyright
Infringement for more information about copyright issues).
* Warranty - Developers or vendors often include disclaimers that they are
not liable for any problem that results from the software being used
incorrectly. They may also protect themselves from liability for
software flaws, software failure, or incompatibility with other programs
on your computer.

The following topics, while not standard, are examples of other conditions
that have been included in EULAs. They present security implications that
you should consider before accepting the agreement.
* Monitoring - Agreeing to the EULA may give the vendor permission to
monitor your computer activity and communicate the information back to
the vendor or to another third party. Depending on what information is
being collected, this type of monitoring could have both security and
privacy implications.
* Software installation - Some agreements allow the vendor to install
additional software on your computer. This may include updated versions
of the software program you installed (the determination of which
version you are running may be a result of the monitoring described
above). Vendors may also incorporate statements that allow them or other
third parties to install additional software programs on your computer.
This software may be unnecessary, may affect the functionality of other
programs on your computer, and may introduce security risks.

Author: Mindi McDowell

Produced 2005 by US-CERT, a government organization.

Note: This tip was previously published and is being re-distributed to increase awareness.

Terms of use

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Monday, June 21, 2010

How Anonymous Are You?

Cyber Security Tip ST05-008
How Anonymous Are You?

You may think that you are anonymous as you browse websites, but pieces of
information about you are always left behind. You can reduce the amount of
information revealed about you by visiting legitimate sites, checking
privacy policies, and minimizing the amount of personal information you

What information is collected?

When you visit a website, a certain amount of information is automatically
sent to the site. This information may include the following:
* IP address - Each computer on the internet is assigned a specific,
unique IP (internet protocol) address. Your computer may have a static
IP address or a dynamic IP address. If you have a static IP address, it
never changes. However, some ISPs own a block of addresses and assign an
open one each time you connect to the internet—this is a dynamic IP
address. You can determine your computer's IP address at any given time
by visiting
* domain name - The internet is divided into domains, and every user's
account is associated with one of those domains. You can identify the
domain by looking at the end of URL; for example, .edu indicates an
educational institution, .gov indicates a US government agency, .org
refers to organization, and .com is for commercial use. Many countries
also have specific domain names. The list of active domain names is
available from the Internet Assigned Numbers Authority (IANA).
* software details - It may be possible for an organization to determine
which browser, including the version, that you used to access its site.
The organization may also be able to determine what operating system
your computer is running.
* page visits - Information about which pages you visited, how long you
stayed on a given page, and whether you came to the site from a search
engine is often available to the organization operating the website.

If a website uses cookies, the organization may be able to collect even more
information, such as your browsing patterns, which include other sites
you've visited. If the site you're visiting is malicious, files on your
computer, as well as passwords stored in the temporary memory, may be at

How is this information used?

Generally, organizations use the information that is gathered automatically
for legitimate purposes, such as generating statistics about their sites. By
analyzing the statistics, the organizations can better understand the
popularity of the site and which areas of content are being accessed the
most. They may be able to use this information to modify the site to better
support the behavior of the people visiting it.

Another way to apply information gathered about users is marketing. If the
site uses cookies to determine other sites or pages you have visited, it may
use this information to advertise certain products. The products may be on
the same site or may be offered by partner sites.

However, some sites may collect your information for malicious purposes. If
attackers are able to access files, passwords, or personal information on
your computer, they may be able to use this data to their advantage. The
attackers may be able to steal your identity, using and abusing your
personal information for financial gain. A common practice is for attackers
to use this type of information once or twice, then sell or trade it to
other people. The attackers profit from the sale or trade, and increasing
the number of transactions makes it more difficult to trace any activity
back to them. The attackers may also alter the security settings on your
computer so that they can access and use your computer for other malicious

Are you exposing any other personal information?

While using cookies may be one method for gathering information, the easiest
way for attackers to get access to personal information is to ask for it. By
representing a malicious site as a legitimate one, attackers may be able to
convince you to give them your address, credit card information, social
security number, or other personal data (see Avoiding Social Engineering and
Phishing Attacks for more information).

How can you limit the amount of information collected about you?

* Be careful supplying personal information - Unless you trust a site,
don't give your address, password, or credit card information. Look for
indications that the site uses SSL to encrypt your information (see
Protecting Your Privacy for more information). Although some sites
require you to supply your social security number (e.g., sites
associated with financial transactions such as loans or credit cards),
be especially wary of providing this information online.
* Limit cookies - If an attacker can access your computer, he or she may
be able to find personal data stored in cookies. You may not realize the
extent of the information stored on your computer until it is too late.
However, you can limit the use of cookies (see Browsing Safely:
Understanding Active Content and Cookies for more information).
* Browse safely - Be careful which websites you visit; if it seems
suspicious, leave the site. Also make sure to take precautions by
increasing your security settings (see Evaluating Your Web Browser's
Security Settings for more information), keeping your virus definitions
up to date (see Understanding Anti-Virus Software for more information),
and scanning your computer for spyware (see Recognizing and Avoiding
Spyware for more information).

Additional information

* Securing Your Web Browser

Author: Mindi McDowell

Produced 2005 by US-CERT, a government organization.

Note: This tip was previously published and is being
re-distributed to increase awareness.

Terms of use

This document can also be found at

For instructions on subscribing to or unsubscribing from this
mailing list, visit