Many people use the free CCleaner program which is used for computer maintenance and file cleanup and it is so popular that millions of downloads take place very week.
Unfortunately Piriform, the company which makes the program, has announced that one of the program versions downloaded by millions of users over a four-week period, had been hacked and has been used to install what is called a ‘back-door Trojan’ virus on people’s systems.
The versions which are affected are CCleaner v5.33.6162 and CCleaner Cloud v1.07.3191 for 32-bit Windows – which were downloadable between 15th August and 22nd September.
The hack allowed the program to cause the download of further unwanted software, possibly including keyloggers and ransomware and initial investigations show that that the program was hacked at the company, before being released to the public using their normal download servers.
Information relating to the infected computer may also have been sent to the hackers servers during this period.
CCleaner users with the above versions should immediately uninstall the program and download the latest version as soon as possible. Although the company states that only the above versions are affected, we recommend uninstalling any version downloaded between those dates before reinstalling, just in case investigations later show that more versions were affected.
We also recommend that if you have the one of the versions mentioned above, you should take the usual common sense precautions such as full scanning of your computer with a good security product, as well as keeping an eye on your bank statements, etc.
This incident is not only potentially serious for users it is also embarrassing for the parent company that now owns Piriform – the antivirus security company Avast. Although further investigations are taking place to find out how this happened, many people may now lose confidence in the CCleaner product.