Cruise operator Carnival Corp., which announced a major ransomware attack on its systems this week, may have experienced at least one more — so far undisclosed — network compromise earlier this year.
According to data from Prevailion, a security vendor that tracks command-and-control activity across the Internet, Carnival's network was likely compromised from at least February through early June.
During that period, an IP address belonging to Carnival was observed regularly communicating with command-and-control (C2) servers outside the company. The rogue beaconing activity was especially high between April 11 and June 5 before subsiding.
Over the duration of the apparent compromise, Prevailion says it observed at least 46,000 attempted connections from the Carnival IP address to the C2 servers. The security vendor identified the activity as associated with Ramnit, a malware that started off as a banking Trojan but more recently has been observed being used to steal credentials as well.
Prevailion CEO Karim Hijazi says his company contacted Carnival about the malicious C2 activity in March, soon after the cruise operator disclosed another breach impacting employee data that had happened in May 2019. Hijazi says Carnival did not respond to Prevailion's attempt to contact them about the malicious activity.
It's not clear whether the beaconing activity Prevailion observed had anything to do with this week's ransomware attack on Carnival, Hijazi says. Also unclear is whether the activity subsided in June because Carnival addressed the issue or because the attackers had used their access to drop some other, stealthier malware on the company's network.
What the data does highlight, however, is Carnival's poor security hygiene, he says. "It does indicate the security here was lax," Hijazi notes.
Prevailion's observations come a day after Carnival disclosed a ransomware attack that resulted in a portion of data belonging to one of the company's brands getting encrypted. Carnival's brands include Princess Cruises, Holland America Line, P&O Cruises, Costa Cruises, AIDA Cruises, and Cunard.
The attack also included at least some customer and employee data being illegally accessed and downloaded. In a Form 8-K regulatory filing, Carnival said its investigation so far shows no other systems were impacted. But the company did not rule out that possibility.
"While the investigation of the incident is ongoing, the Company has implemented a series of containment and remediation measures to address this situation and reinforce the security of its information technology systems," Carnival said.
When contacted by Dark Reading for comment on Prevailion's claims, Roger Frizzell, Carnival's chief communications officer, pointed to the details in the regulatory filing. "We are not planning to comment beyond the information in the 8K," he says.
Carnival is the latest in a long, growing list of organizations to fall victim to a ransomware attack. Many of the attacks have caused substantial downtime for the victims. A June ransomware attack on Honda, for instance resulted in the automaker having to temporarily suspend production operations at some of its plants worldwide.
Others have ended up paying substantial ransoms to get back access to encrypted data. The University of California San Francisco paid about $1.14 million in June to get back its data after attackers dropped ransomware on several critical systems at the university's School of Medicine. Multiple other universities were hit in the same campaign, including Columbia College and Michigan State University.
In addition to having to deal with encrypted data and the resulting operational disruption, many ransomware victims — including Carnival — increasingly have to contend with data theft. Ransomware operators have recently begun stealing data from victims — in addition to encrypting it — and then threatening to publicly release the information if not paid.