Malware means “malicious software”. This means all programmes that can damage device software, such as computer viruses. However, malware also includes spyware, which shares personal details saved on the computer with other people. Other forms of malware include adware, which launches “pop up” advertisements, and worms, which fill up hard disk space.
Malware “infection” causes different problems, depending on the type of malware and the device involved, (PC, laptop, SMART phone, tablet etc.). Some malware programmes do no apparent harm at all, apart from spreading themselves using the infected device or user. Others send passwords, keystrokes, details of browsing history or stored personal details to a “remote user”, (i.e. someone in a different location). Yet other malware may give a remote user control of a device, including the keyboard, mouse or webcam. Malware can also stop devices working at all by corrupting their operating system.
Malware spreads in a range of ways. Worms “crawl” through network connections, including internet and Wi-Fi connections. To prevent these, the user must install firewall software. This software monitors and controls information entering and leaving the network or connection.
Sometimes users download malware by accident. Trojan Horse malware is “hidden inside” a file the user wants to download deliberately, (e.g. a game or an email attachment). Once the user has downloaded the file, the hidden Trojan Horse software runs itself and infects the device. Other users download malware accidentally when they visit certain websites. Whenever a user visits a web site, their device downloads the HTML files, images etc. that make up each webpage and stores them in the internet cache. Unfortunately, this means that the device will also download any malware hidden in the webpage files.
Malware can also be concealed in files saved on removable media such as USB Flash Drives, (memory sticks), and CDs/ DVDs. For this reason, students, (apart from Sixth Form), are not allowed to use their own removable media in school devices. Any files that a student needs downloaded/ uploaded must be checked for malware and transferred to the student’s network drive by ICT Technical staff.
The commonest type of malware seen in our school spreads through the email system. The malware appears as an email, which can have any subject and is usually from a contact. The mail has a button or link in the message body. If a user clicks the link, the malware infects the device. The malware will also send itself as an email to some or all of the user’s contacts. Since many of our school users have large numbers of contacts, theoretically the whole school community, this type of malware can spread very quickly.
No method can protect a device against malware completely. However, the simplest way to avoid most malware is to follow these guidelines.
- Delete emails with suspicious links or buttons and not click these links!
- Delete emails with attachments that were not expected or that come from senders they do not recognise or trust.
- Download software from official websites and not use pirated copies.
- Scan flash drives and other removable media with antivirus software before use.
- Ignore free advertisements and pop ups; clicking these is a common cause of malware infection.
Installing firewall software will prevent worms entering a networked system. Installing antivirus software and using it to scan devices will also detect and remove malware from infected devices. Users must regularly update the software, because new malware is appearing all the time. Free, automatically updated antivirus software is available from the internet.