#Ccleaner malware c2 server reinstall update#
#Ccleaner malware c2 server reinstall software#

For a period of time, the legitimate signed version of CCleaner 5.33 being distributed by Avast also contained a multi-stage malware payload that rode on top of the installation of CCleaner.

#Ccleaner malware c2 server reinstall software#

Talos recently observed a case where the download servers used by software vendor to distribute a legitimate software package were leveraged to deliver malware to unsuspecting victims. Luckily with tools like AMP the additional visibility can usually help direct attention to the initial vector. Frequently, as with Nyetya, the initial infection vector can remain elusive for quite some time. The Nyetya worm that was released into the wild earlier in 2017 showed just how potent these types of attacks can be. This trust relationship is then abused to attack organizations and individuals and may be performed for a number of different reasons. This is because with supply chain attacks, the attackers are relying on the trust relationship between a manufacturer or supplier and a customer. Supply chain attacks are a very effective way to distribute malicious software into target organizations.

#Ccleaner malware c2 server reinstall update#

Update 9/18: CCleaner Cloud version is also reported to be affected This post was authored by: Edmund Brumaghin, Ross Gibb, Warren Mercer, Matthew Molyett, and Craig Williams Update, 8:30AM ET: Article updated with Avast statement.ĬCleanup: A Vast Number of Machines at Risk It’s a trend that many security researches will be monitoring closely, to catch the latest innovative ways that hackers are breaching multiple systems. Hackers appear to be targeting these types of distribution points to more easily spread malware, instead of the traditional way of attacking individual machines themselves.

“By exploiting the trust relationship between software vendors and the users of their software, attackers can benefit from users' inherent trust in the files and web servers used to distribute updates,” says Talos.Įarlier this year, Ukrainian company MeDoc was breached and its update servers used to distribute the Petya ransomware. This is an unusual attack as software similar to CCleaner is trusted by consumers and meant to remove “crapware” from a system.

'An unusual attack on software update mechanisms' “Piriform believes that these users are safe now as its investigation indicates it was able to disarm the threat before it was able to do any harm,” says an Avast spokesperson. 2.27 million users have been affected by the attack, and Avast Piriform believes it was able to prevent the breach harming customers. Dubbed “crap cleaner,” it’s designed to wipe out cookies and offer some web privacy protections. “For a period of time, the legitimate signed version of CCleaner 5.33 being distributed by Avast also contained a multi-stage malware payload that rode on top of the installation of CCleaner,” says the Talos team.ĬCleaner has been downloaded more than 2 billion times according to Avast, making it a popular target for hackers. Security researchers at Cisco Talos discovered that download servers used by Avast (the company that owns CCleaner) were compromised to distribute malware inside CCleaner. Hackers have successfully breached CCleaner’s security to inject malware into the app and distribute it to millions of users.