Threat Signal Report

AcidRain Wiper Suspected in Satellite Broadband Outage in Europe

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FortiGuard Labs is aware a report that a new wiper malware was deployed and destroyed data on modems and routers for KA-SAT satellite broadband services, resulting in service outages across Europe on February 24th, 2022. The service interruption also caused the disconnection of remote access to 5,800 wind turbines in Europe. According to security vendor SentinelOne, AcidRain wiper shares similarities with a VPNFilter stage 3 destructive plugin. The Federal Bureau of Investigation (FBI) and Department of Justice disrupted the VPNFilter botnet by seizing a domain that was part of the Command-and-Control (C2) infrastructure. The Russian-connected the Sofacy threat actor (also known as APT28, Sednit, Pawn Storm, Fancy Bear, and Tsar) is believed to have operated the VPNFilter botnet.

Why is this Significant?
This is significant not only because a new wiper malware was used in the attack but also because the attack caused service interruption for satellite broadband services in Europe, including Ukraine, and 5,800 wind turbines in Europe were knocked offline.

Also, the U.S. Cybersecurity and Infrastructure Security Agency (CISA) and the FBI released a joint advisory on March 17th, 2022, warning of cyberattacks on U.S. and international satellite communication (SATCOM) networks.

What Happened?

According to the statement released by Viasat, a provider of KA-SAT satellite broadband services, the attack occurred in two phases.

1. On February 24th, 2022, "malicious traffic were detected emanating from several SurfBeam2 and SurfBeam 2+ modems and/or associated customer premise equipment (CPE) physically located within Ukraine and serviced by one of the KA-SAT consumer-oriented network partitions. This targeted denial of service attack made it difficult for many modems to remain online."

2. Then, the company started to observe a gradual decline of the connected modems. Subsequently, a large number of additional modems across much of Europe exited the network and they did not re-enter to the network.

The statement continues as saying that the attacker gained remote access to the trusted management segment of the KA-SAT network through a misconfigured VPN appliance. The threat actor moved laterally through the network and ultimately sent "legitimate, targeted management commands on a large number of residential modems simultaneously. Specifically, these destructive commands overwrote key data in flash memory on the modems, rendering the modems unable to access the network, but not permanently unusable."

The belief is that "these destructive commands" refer to AcidRain wiper malware.

What is VPNFilter malware?

VPNFilter is a IoT malware that was first reported in mid-2018 and targeted home and Small Office/Home Office (SOHO) routers and Network Attached Storage (NAS) devices. The malware is not only capable of performing data exfiltration but also rendering devices completely inoperable.

FortiGuard Labs published a research blog series on VPNFilter malware in 2018. See the Appendix for a link to "VPNFilter Malware - Critical Update" and

"VPNFilter Update - New Attack Modules Documented".

What is the threat actor Sofacy?

Sofacy is a threat actor who is believed to operate for Russian interests. The threat actor has been in operation since at least 2007 and targets a wide range of sectors including government, military and security organizations.

One of the most infamous activities carried out by the Sofacy group is their alleged involvement in hacking "networks and endpoints associated with the U.S. election" in 2016, in which the FBI the US Department of Homeland Security (DHS) released a join advisory on December 29th, 2016.

What is the Status of Coverage?

FortiGuard Labs provides the following AV coverage against AcidRain wiper malware believed to have been used in the attack:



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