Avast CTO Explains What Went Wrong in CCleaner Attack

Published: Apr 19, 2018
Updated: Feb 2, 2021
2 minute read
Avast CTO
eWeek のコンテンツおよび製品のおすすめは、編集上の独立性を保っています。パートナーへのリンクをクリックすると、当社が報酬を得る場合があります。 詳細を見る

SAN FRANCISCO—The importance of doing cyber-security due diligence prior to acquiring a company is something that security vendor Avast learned the hard way.

In September 2017 the CCleaner tool that is widely used by consumers was found to have been injected with malware by hackers. The malware discovery came months after Avast acquired Pirifom, the company that makes CCleaner.  

In a video interview with eWEEK at the RSA Conference here, Ondrej Vlcek CTO of Avast provided insight into what happened in that incident and best practices so others can avoid the same issue.


According to Avast’s analysis, the Piriform compromise was a supply-chain attack that likely started as early as March of 2017 and wasn’t detected until September 2017.

“We bought the company while it was being hacked,” Vlcek told eWEEK.  


Lessons Learned

“When doing M&A (mergers and acquisitions) cyber-due diligence is a no brainer, ” Vlcek said. 

He noted that most companies focus just on the financial and legal aspects of a company they plan to acquire, but that’s not enough in the modern threat landscape. 

Another key lesson is that in a supply chain attack, relying on digital signatures might not be the best approach to guaranteeing code integrity. Vlcek said that many endpoint security products whitelist technologies that have been digitally signed by a software developer. In the CCleaner attack, that hackers were able to inject themselves in the supply chain and the the maliciously modified code was still signed by the original certificate.

Vlceck said that Avast has added additional capabilities to its products to address the CCleaner type of attack in the future.

Watch the video interview with Vlcek above.

Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.

Sean Michael Kerner

Sean Michael Kerner is an Internet consultant, strategist, and writer for several leading IT business web sites.

eWeek Logo

eWeek has the latest technology news and analysis, buying guides, and product reviews for IT professionals and technology buyers. The site's focus is on innovative solutions and covering in-depth technical content. eWeek stays on the cutting edge of technology news and IT trends through interviews and expert analysis. Gain insight from top innovators and thought leaders in the fields of IT, business, enterprise software, startups, and more.

TechnologyAdvice が所有・運営しています。 © 2026 TechnologyAdvice. 無断転載を禁じます

広告主に関する開示:このサイトに掲載されている製品の一部は、TechnologyAdvice が報酬を受け取っている企業のものです。この報酬は、製品がこのサイトのどこにどのように表示されるか(表示される順序など)に影響する場合があります。TechnologyAdvice は、市場で入手可能なすべての企業やすべての種類の製品を掲載しているわけではありません。