Downloading photos from the Internet is unlikely to harm your computer, because image files do not contain executable code, making it virtually impossible for a virus to hide inside an image. Viruses can sometimes look like image files using dual file extensions, like “file.jpg.exe”, and some image hosting sites can also contain malware. Users should also be aware of copyright law when downloading photos for personal or commercial use.
Downloading photos is generally safe because images do not have executable code.
Computer files may contain executable code that runs as a program or static information intended to be read by other software. Image files fall into the latter category and are not designed to contain executable code. Since computer viruses, worms, and other forms of malware run as executable programs, it is unlikely that someone trying to download photos is putting your computer at risk. It is at least theoretically possible for an attacker to deliberately create a corrupted image file that would crash or tamper with the program opening the file, but this type of attack is very rare.
A more significant threat comes from executable programs disguised as image files, a tactic used by some virus and malware authors to disguise their malicious creations. One virus that was particularly effective in this type of scam was spread through email messages with an attachment called “AnnaKournikova.jpg.vbs”. Although the file name contains “.jpg”, which is a valid extension for an image, the actual file extension was “.vbs”, an executable format. As a result, anyone trying to download photos of the Russian tennis star was actually opening a virus that sent copies of itself for every entry in the user’s calendar. Actual image files only end in “.jpg”, “.gif” or “.png”. All other extensions should be avoided.
Some websites that offer the ability to download photos may try to secretly install malware or spyware on the user’s system. These sites may be set up with the intention of targeting visitors or they may be legitimate sites that have been hacked. Common sense security precautions like keeping your software up to date can help alleviate the risk of malware infection.
Even if found through a search engine or displayed on a public website, it’s also important to realize that photos on the Internet may be protected by copyright laws. Downloading these photos for a school presentation, sharing them with friends, or using them on your own website may be a form of copyright infringement. It is especially important to determine the copyright status of an image if it is used for commercial purposes. Some sites publish content under a less restrictive license that allows users to download photos for certain uses. A search for “Creative Commons” or “Public Domain Images” can help keep users out of harm’s way.
