Ransom attack hits before holiday

Businesses around the world rushed Saturday to contain a ransomware attack that has paralyzed their computer networks, a situation complicated in the U.S. by offices lightly staffed at the start of the Fourth of July holiday weekend.

It’s not yet known how many organizations have been hit by demands that they pay a ransom in order to get their systems working again. But some cybersecurity researchers predict the attack targeting customers of software supplier Kaseya could be one of the broadest ransomware attacks on record — even after a scourge of headlinegrabbing attacks over recent months.

“The number of victims here is already over a thousand and will likely reach into the tens of thousands,” said cybersecurity expert Dmitri Alperovitch of the Silverado Policy Accelerator think tank. “No other ransomware campaign comes even close in terms of impact.”

The cybersecurity firm ESET says there are victims in least 17 countries, including the United Kingdom, South Africa, Canada, Argentina, Mexico and Spain.

In Sweden, most of the grocery chain Coop’s 800 stores were unable to open because their cash registers weren’t working, according to SVT, the country’s public broadcaster. The Swedish State Railways and a major local pharmacy chain were also affected.

Cybersecurity experts say the REvil gang, a major Russianspeaking ransomware syndicate, appears to be behind the attack that targeted Kaseya, using its networkmanagement package as a conduit to spread the ransomware through cloudservice providers. Kaseya CEO Fred Voccola said in a statement that the company believes it has identified the source of the vulnerability and will “release that patch as quickly as possible to get our customers back up and running.”

Voccola said fewer than 40 of Kaseya’s customers were known to be affected, but experts said the ransomware could still be affecting hundreds more companies that rely on Kaseya’s clients that provide broader IT services. John Hammond of the security firm Huntress Labs said he was aware of a number of managedservices providers — companies that host IT infrastructure for multiple customers — being hit by the ransomware, which encrypts networks until the victims pay off attackers.

“It’s reasonable to think this could potentially be impacting thousands of small businesses,” said Hammond, basing his estimate on the service providers reaching out to his company for assistance and comments on Reddit showing how others are responding.

At least some victims appeared to be getting ransoms set at $45,000, considered a small demand but one that could quickly add up when sought from thousands of victims, said Brett Callow, a ransomware expert at the cybersecurity firm Emsisoft.

Voccola said the problem is only affecting its “onpremise” customers, which means organizations running their own data centers. It’s not affecting its cloudbased services running software for customers, though Kaseya also shut down those servers as a precaution, he said.

The company added in a statement Saturday that “customers who experienced ransomware and receive a communication from the attackers should not click on any links — they may be weaponized.”

Complicating the response is that it happened at the start of a major holiday weekend in the U.S., when most corporate IT teams aren’t fully staffed.

The federal Cybersecurity and Infrastructure Security Agency said in a statement that it is closely monitoring the situation and working with the FBI to collect more information about its impact.

The privately held Kaseya is based in Dublin, Ireland, with a U.S. headquarters in Miami.