Pierluigi Paganini December 07, 2023

The UK NCSC and Microsoft warned that Russia-linked threat actor Callisto Group is targeting organizations worldwide.

The UK National Cyber Security Centre (NCSC) and Microsoft reported that the Russia-linked APT group Callisto Group is targeting organizations worldwide. The nation-state actor is carrying out spear-phishing attacks for cyberespionage purposes.

The Callisto APT group (aka “Seaborgium“, “Star Blizzard”, “ColdRiver”, “TA446”) targeted government officials, military personnel, journalists and think tanks since at least 2015.

In the past, the group’s activity involved persistent phishing and credential theft campaigns leading to intrusions and data theft. The APT primarily targets NATO countries, but experts also observed campaigns targeting the Baltics, Nordics, and Eastern Europe regions, including Ukraine.

This week, the Reddit security team the leak of US-UK trade documents through its platform to a coordinated information campaign linked to Russia.

“We were recently made aware of a  that included leaked documents from the UK,” the statement said. “We investigated this account and the accounts connected to it, and today we believe this was part of a campaign that has been reported as originating from Russia.”

“Earlier this year Facebook discovered a  on its platform, which was further analyzed by the Atlantic Council and dubbed ‘,’” Reddit’s announcement said. “Suspect accounts on Reddit were recently reported to us, along with indicators from law enforcement, and we were able to confirm that they did indeed show a pattern of coordination.”

According to a press release published by the UK government, the UK and its allies observed a series of attempts by the Russian Intelligence Services to target high-profile individuals and entities through cyber operations. The nation-state actor aimed at obtaining information to interfere in UK politics and democratic processes.   

The UK Government linked the activity to Centre 18, a unit within Russia’s Intelligence Services FSB tracked as  Star Blizzard.

“While some attacks resulted in documents being leaked, attempts to interfere with UK politics and democracy have not been successful.” reads the press release. ” The group has also selectively leaked and amplified the release of information in line with Russian confrontation goals, including to undermine trust in politics in the UK and likeminded states.”

The UK believes that the FSB coordinated at least the following activities:

• Cyber attacks against parliamentarians from multiple political parties since at least 2015.
• The theft of UK-US trade documents leaked before the 2019 General Election. The leak was previously attributed to the Russian state via a Written Ministerial Statement in 2020.
• The 2018 hack of the Institute for Statecraft, a UK think tank engaged in initiatives to safeguard democracy against disinformation. The state-sponsored hackers gained access to the account of its founder Christopher Donnelly from December 2021.
• Attacks against universities, journalists, the public sector, non-governmental organizations, and other civil society organizations, many of which play a crucial role in UK democracy.

The National Crime Agency investigation identifies two members of Star Blizzard and the UK and US governments sanctioned them. The two individuals are:

• Ruslan Aleksandrovich PERETYATKO, who is a Russian FSB intelligence officer and a member of Star Blizzard AKA the Callisto Group 
• Andrey Stanislavovich KORINETS, AKA Alexey DOGUZHIEV, who is a member of Star Blizzard AKA the Callisto Group 

“The Foreign, Commonwealth and Development Office has also summoned the Russian Ambassador to express the UK’s deep concern about Russia’s sustained attempts to use cyber to interfere in political and democratic processes in the UK and beyond.” concludes the press release. 

The Microsoft Threat Intelligence team also technical details about Star Blizzard tactics, techniques, and procedures (TTPs).

The operations of Star Blizzard continue to concentrate on the theft of email credentials, with a primary emphasis on targeting cloud-based email providers hosting both organizational and personal email accounts.

Microsoft has identified five new Callisto Group (Star Blizzard) evasive techniques:

• Use of server-side scripts to prevent automated scanning of actor-controlled infrastructure.
• Use of email marketing platform services to hide true email sender addresses and obviate the need for including actor-controlled domain infrastructure in email messages
• Use of a DNS provider to obscure the IP addresses of actor-controlled virtual private server (VPS) infrastructure. Once notified, the DNS provider took action to mitigate actor-controlled domains abusing their service.
• Password-protected PDF lures or links to cloud-based file-sharing platforms where PDF lures are hosted
• Shifting to a more randomized domain generation algorithm (DGA) for actor-registered domains

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(SecurityAffairs – hacking, Callisto Group)