Almost 250,000 computers worldwide have been infected with CryptoLocker since it emerged in April and it has so far been used to extort payments of more than €27m, according to the FBI. Industry experts have been quick to back up the stern message from the National Crime Agency, whose advice to visit internet awareness group Get Safe Online’s website led to the site going down for 15 hours.
Below are some methods experts recommend to protect yourself from GameOver Zeus and CryptoLocker, and remove it if you suspect your computer is infected:
Update your computer programmes – especially anti-virus software
The NCA has advised that people ensure their security software is installed and updated, and that they run scans. Users should also check that their computer operating systems and applications, in general, are up to date.
Microsoft users can do this by using the ‘Check for Updates’ function on Windows Update, while Mac users can choose ‘Software Update’ on the System Preferences menu.
Beware of suspicious emails
Do not open email attachments unless you are certain they are authentic. Potentially harmful emails generally have some or all of the following characteristics according to Get Safe Online:
- You don’t know the sender.
- The message contains misspellings (for example using a zero instead of an ‘o’) designed to fool spam filters.
- It makes an offer that seems too good to be true.
- The subject line and contents do not match.
- Contains an urgent offer end date (for example “Buy now and get 50% off”).
- Contains a request to forward an email to multiple people, and may offer money for doing so.
- Contains a virus warning.
- Contains attachments, which could include .exe files.
- Contains a request from a Bank to fill out forms or provide information.
Change your passwords
If your computer gets hacked, your original passwords may have been compromised by GameOver Zeus and CryptoLocker, and could be used to harvest any important information you store or access on your computer.
Back up your files
All of your files, including photos and documents, should be regularly saved to an online backup provider such as www.sleepless.ie and not stored on a connected external piece of hardware, such as a USB stick or an external hard drive. This means it will not be lost if your computer is attacked, or if it breaks. Any devices connected to your computer during an attack will also be compromised.
The US Government has recommended a number of remediation tools which can be used to remove GameOver Zeus. These include F-Secure (for Windows Vista, 7 and 8 or Windows XP), Heimdal (for Microsoft Windows XP, Vista, 7, 8 and 8.1), and Kaspersky if you fear your computer is infected.