informa
3 min read
article

How Anthem Shared Key Markers Of Its Cyberattack

Insurer shared the MD5 malware hashes, IP addresses, and email addresses used by its attackers.

Anthem isn't a member of the healthcare industry's information sharing and analysis center, the NH-ISAC, so the NH-ISAC got word of the attack via other members of the threat information-sharing community the morning after Anthem reported its massive data breach.

The NH-ISAC then confirmed and validate with Anthem the indicators of compromise that it had received that morning via its members. "We got the information from participating members. Once we received it, we did confirm with Anthem," says Josh Singletary, NH-ISAC CIO, who heads up intelligence operations. That information then was pushed out to other ISACs as well, he says. The ISAC pushed the indicators of compromise via email to its members as well as via its secure portal, which some members use to incorporate them into their IDS/IPSes, firewalls, and other systems.

The process of how Anthem's attack markers were shared among the healthcare industry and other relevant groups and organizations provides a rare peek at how potential victims are notified about the latest threat emerging from a major breach. As attacks and attack campaigns intensify and multiply, intelligence-sharing groups like ISACs and others are crunched to get usable information and intelligence to their members quickly so they can shore up their defenses and prevent becoming the next victims.

Anthem, meanwhile, shared with HITRUST's Cyber Threat Intelligence and Incident Coordination Center the MD5 malware hashes, IP addresses, and email addresses used by its attackers. As of now, only HITRUST has all of the Anthem attack IOCs, the organization says. Within an hour of getting that attack information from Anthem, HITRUST fed that information to its automated cyber threat exchange, as well as with US-CERT, the Department of Homeland Security, and the Department of Health and Human Services.

"This crucial observable information was anonymously shared with the HITRUST C3 Community, through the automated threat exchange. It was quickly determined that the IOCs were not found by other organizations across the industry and this attack was targeted at a specific organization," according to an alert issued by HITRUST last week. "Upon further investigation and analysis it is believed to be a targeted advanced persistent threat (APT) actor. With that information, HITRUST determined it was not necessary to issue a broad industry alert."

The NH-ISAC took a different tack, sharing not only within the ISAC but with other ISACs, too. So far, there's been no sign or confirmation of other healthcare organizations in the NH-ISAC getting hit by the same attack Anthem suffered. But several security experts say that if the attackers are indeed a Chinese cyberespionage group, there would be other victims as well given the region's widespread and pervasive tactics in these types of attacks.

"We're not seeing any of those [indicators of compromise from the Anthem breach], so that's really good," says Rich Reybok, CTO of Vorstack, which provides an automation and collaboration platform to the NH-ISAC.

Anthem's attack, while targeted, in many ways was very similar to others out there in its methods and approach.

"What was different about this attack was how massive it was, how many records--80 million--affected. It has really raised awareness in the healthcare sector and other sectors on how critical intelligence- and information-sharing and coordinated response is," says Deborah Kobza, founder & CEO of NH-ISAC.

NH-ISAC's Kobza says once word got out about the Anthem breach, members of the ISAC started offering to help other members who needed the extra support. "Even their own resources and security teams to help any organization who may have been impacted by this type of attack," she says.