• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Techransomware

Hackers in Saturday’s ‘sophisticated’ ransomware attack targeted flaw in IT management software

By
Jordan Robertson
Jordan Robertson
,
William Turton
William Turton
, and
Bloomberg
Bloomberg
Down Arrow Button Icon
By
Jordan Robertson
Jordan Robertson
,
William Turton
William Turton
, and
Bloomberg
Bloomberg
Down Arrow Button Icon
July 5, 2021, 12:51 AM ET

The hackers behind a mass ransomware attack exploited multiple previously unknown vulnerabilities in IT management software made by Kaseya Ltd., the latest sign of the skill and aggressiveness of the Russia-linked group believed responsible for the incidents, cybersecurity researchers said Sunday.

Marcus Murray, founder of Stockholm-based TrueSec Inc., said his firm’s investigations involving multiple victims in Sweden found that the hackers targeted them opportunistically. In those cases, the hackers used a previously unknown flaw in Miami-based Kaseya’s code to push ransomware to servers that used the software and were connected to the Internet, he said.

The Dutch Institute for Vulnerability Disclosure said it had alerted Kaseya to multiple vulnerabilities in its software that were then used in the attacks, and that it was working with the company on fixes when the ransomware was deployed.

Subscribe to Data Sheet, a daily brief on the business of tech, delivered free to your inbox.

Kaseya “showed a genuine commitment to do the right thing,” the Dutch organization wrote. “Unfortunately, we were beaten by REvil in the final sprint, as they could exploit the vulnerabilities before customers could even patch,” it added, referring to the Russia-based hacking group. REvil was accused of being behind the May 30 ransomware attack of meatpacking giant JBS SA.

The findings differentiate the latest incident—which cybersecurity firm Huntress Labs Inc. said affected more than 1,000 businesses—from other recent assaults on the software supply chain. For instance, an attack the U.S. blamed on Russia’s foreign intelligence service, disclosed in December, involved altered software updates from another provider of IT management software, Austin, Texas-based SolarWinds Corp. Ultimately, nine federal agencies and at least 100 companies were infiltrated via SolarWinds and other methods.

Determined

Regarding the most recent attack, Frank Breedijk, head of the Dutch institute’s computer security incident response team, emphasized the hackers’ high skill level in exploiting the Kaseya software.

“The big point behind this is someone was willing, determined and had the resources to build this attack chain, and it’s not a trivial chain to build,” he said in an interview. “You have to know what you’re doing to make an attack like this work.”

Kaseya spokesperson Dana Liedholm confirmed in an e-mail that the incident involved multiple vulnerabilities in the company’s products and called it a “sophisticated weaponized attack with ransomware.” “This was not as simple as a single 0-day exploit,” Liedholm said, using an industry term for vulnerabilities in software that hackers are aware of but that the makers of that code are not.

Kaseya said its VSA product was the victim of a “sophisticated cyberattack” and that it had notified the FBI. Kaseya has identified fewer than 40 customers impacted by the attack, adding that its cloud-based services weren’t impacted. In a later statement Sunday, the firm said it’s working with FireEye Inc. and other security companies to help manage the fallout.

Not Difficult

The U.S. Cybersecurity and Infrastructure Security Agency also said it was continuing to respond to the recent attack, which it said leveraged a “vulnerability in Kaseya VSA software against multiple managed service providers (MSPs) and their customers.”

Kaseya’s customers include companies that provide remote IT support and cybersecurity services for small- and medium-sized businesses.

In the latest attack, the hackers had to target machines individually. That’s not complicated. Hackers and security researchers have access to many of the same basic tools for scanning the Internet looking for computers that are vulnerable to attack. But by infecting IT support organizations, the malicious software was passed to their customers as well, multiplying the impact.

One of the known victims—Swedish grocery chain Coop—said Saturday that most of its more than 800 stores couldn’t open because the attack led to a shutdown of their payment terminals. Others include managed service providers, which provide IT services to other businesses, meaning their infections may have spread to their customers.

One of the MSPs affected was Avtex LLC, which said it detected the ransomware attack on Friday morning that appeared to have originated through Kaseya. “Avtex’s security engineers immediately alerted Kaseya to the severity of the issue and proceeded to activate proactive and precautionary measures to safeguard its clients and its infrastructure,” Avtex said in a statement, adding that its systems are all fully operations and it has seen no evidence of any data breach.

Clever Targeting

Murray, of Sweden’s TrueSec, declined to identify any of his firm’s clients. He said because of Kaseya’s central role in managing security and IT that victims could have longer recovery times than in typical ransomware incidents.

“The tool these organizations are using normally for patching and IT support and recovery is Kaseya,” he said. “It’s a big undertaking when someone takes away all your ability to do the maintenance.”

“From a criminal standpoint it’s a brilliant supply-chain target to take away the tool that’s needed to recover from the threat,” Murray added. “They’re not only encrypting the systems but they’re also taking the recovery tool out of the equation.”

Ross McKerchar, vice president and chief information security officer at the cybersecurity firm Sophos, said the hack was “one of the farthest reaching criminal ransomware attacks Sophos has ever seen.”

“At this time, our evidence shows that more than 70 managed service providers were impacted, resulting in more than 350 further impacted organizations,” he said in a statement. “We expect the full scope of victim organizations to be higher than what’s being reported by any individual security company.”

There are victims in 17 countries so far, including the U.K., South Africa, Canada, Argentina, Mexico and Spain, according to Aryeh Goretsky, a researcher at cybersecurity firm ESET.

President Joe Biden said Saturday that he had ordered ordered a “deep dive” from the intelligence community about the incident, which came just weeks after Biden implored Russian President Vladimir Putin at a summit on June 16 to curb cyberattacks against the U.S. Biden said “we’re not sure” that Russia is behind the attack. The president said he expects to know more about the attacks on Sunday.

“The initial thinking was, it was not the Russia government, but we’re not sure yet,” he said.

Subscribe to Fortune Daily to get essential business stories straight to your inbox each morning.
About the Authors
By Jordan Robertson
See full bioRight Arrow Button Icon
By William Turton
See full bioRight Arrow Button Icon
By Bloomberg
See full bioRight Arrow Button Icon

Latest in Tech

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Tech

Image showing multiple computer screens with code.
CybersecuritySecurity
Mercor, a $10 billion AI startup that works with companies including OpenAI and Anthropic, confirms major data breach
By Beatrice NolanApril 2, 2026
8 hours ago
picture of the word "solana"
CryptoCryptocurrency
Latest crypto hack sees thieves make off with $280 million from Solana DeFi platform Drift
By Carlos GarciaApril 2, 2026
8 hours ago
Jack Dorsey and Roelof Botha think AI can make middle management obsolete 
AIBlock
Jack Dorsey and Roelof Botha think AI can make middle management obsolete 
By Jacqueline MunisApril 2, 2026
10 hours ago
china
AIChina
Meet China’s AI-powered recycling robot that sorts 220 pounds of clothes in 2 to 3 minutes
By Tian MacLeod Ji and The Associated PressApril 2, 2026
10 hours ago
In the age of vibe coding, trust is the real bottleneck
AIEye on AI
In the age of vibe coding, trust is the real bottleneck
By Sharon GoldmanApril 2, 2026
11 hours ago
A photo illustration of two laptops with eyeballs over a red background with alert signs.
CryptoNorth Korea
I knew about North Korean hackers—they still tricked me and got into my computer
By Ben WeissApril 2, 2026
11 hours ago

Most Popular

Gen Z fled San Francisco for Texas and Florida. Now they’re turning ‘welcomer cities’ into the next big tech towns
Real Estate
Gen Z fled San Francisco for Texas and Florida. Now they’re turning ‘welcomer cities’ into the next big tech towns
By Fortune EditorsApril 2, 2026
19 hours ago
Current price of gold as of April 1, 2026
Personal Finance
Current price of gold as of April 1, 2026
By Fortune EditorsApril 1, 2026
2 days ago
Two-thirds of parents say their adult Gen Z kids still rely on them financially  for support—even though it's putting them under strain
Success
Two-thirds of parents say their adult Gen Z kids still rely on them financially  for support—even though it's putting them under strain
By Fortune EditorsMarch 31, 2026
2 days ago
The tax escape map: Billionaires are bolting for Florida from the West Coast and taking billions in tax revenue with them
Real Estate
The tax escape map: Billionaires are bolting for Florida from the West Coast and taking billions in tax revenue with them
By Fortune EditorsApril 2, 2026
20 hours ago
Deutsche Bank asked AI if it’s true that AI will solve the economy’s inflation problems. The robots answered
Economy
Deutsche Bank asked AI if it’s true that AI will solve the economy’s inflation problems. The robots answered
By Fortune EditorsApril 1, 2026
1 day ago
Major 4-day workweek study suggests that when we work 5 days we spend one doing basically nothing
Success
Major 4-day workweek study suggests that when we work 5 days we spend one doing basically nothing
By Fortune EditorsApril 2, 2026
12 hours ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.