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.

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