Microsoft Uncovers ‘Moonstone Sleet’ — New North Korean Hacker Group

A never-in advance of-viewed North Korean threat actor codenamed Moonstone Sleet has been attributed as guiding cyber attacks targeting individuals and businesses in the software package and information technology, training, and defense industrial base sectors with ransomware and bespoke malware previously linked with the infamous Lazarus Group.

“Moonstone Sleet is noticed to set up faux organizations and task opportunities to have interaction with likely targets, employ trojanized variations of respectable instruments, generate a destructive game, and supply a new customized ransomware,” the Microsoft Threat Intelligence group stated in a new investigation.

It also characterized the risk actor as working with a mixture of experimented with-and-correct techniques used by other North Korean danger actors and distinctive attack methodologies to fulfill its strategic goals.

The adversary, hitherto tracked by Redmond less than the emerging cluster moniker Storm-1789, is assessed to be a point out-aligned team that at first exhibited sturdy tactical overlaps with the Lazarus Group (aka Diamond Sleet), before developing its individual distinct identity by means of different infrastructure and tradecraft.

The similarities with Lazarus incorporate extensively reusing code from recognized malware this sort of as Comebacker, which was initially noticed in January 2021 in link with a marketing campaign concentrating on security researchers functioning on vulnerability investigation and enhancement.

Comebacker was put to use by the Lazarus Team as a short while ago as this February, embedding it inside of seemingly innocuous Python and npm offers to build contact with a command-and-regulate (C2) server to retrieve added payloads.

To help its varied ambitions, Moonstone Sleet is also regarded to go after work in software package growth positions at various respectable providers, possible in an try to make illicit profits for the sanctions-strike place or attain covert accessibility to businesses.

Attack chains observed in August 2023 associated the use of a modified edition of PuTTY – a tactic adopted by the Lazarus Team in late 2022 as part of Operation Aspiration Job – by way of LinkedIn and Telegram as perfectly as developer freelancing platforms.

“Generally, the actor despatched targets a .ZIP archive that contains two documents: a trojanized variation of putty.exe and url.txt, which contained an IP address and a password,” Microsoft reported. “If the furnished IP and password were entered by the consumer into the PuTTY application, the application would decrypt an embedded payload, then load and execute it.”

The trojanized PuTTY executable is created to drop a customized installer dubbed SplitLoader that initiates a sequence of intermediate stages in purchase to ultimately start a Trojan loader which is responsible for executing a portable executable been given from a C2 server.

Alternate attack sequences have entailed the use of destructive npm packages that are delivered via LinkedIn or freelancing sites, generally masquerading as a bogus corporation to deliver .ZIP files invoking a malicious npm bundle underneath the guise of a technological expertise evaluation.

These npm deals are configured to hook up to an actor-managed IP handle and drop payloads identical to SplitLoader, or aid credential theft from the Windows Nearby Security Authority Subsystem Service (LSASS) method.

It can be value noting that the targeting of npm builders using counterfeit deals has been related with a marketing campaign earlier documented by Palo Alto Networks Unit 42 less than the identify Contagious Job interview (aka DEV#POPPER). Microsoft is tracking the action below the title Storm-1877.

Rogue npm deals have also been a malware shipping vector for a further North Korea-linked team codenamed Jade Sleet (aka TraderTraitor and UNC4899), which has been implicated in the JumpCloud hack last calendar year.

Other attacks detected by Microsoft because February 2024 have utilized a malicious tank video game named DeTankWar (aka DeFiTankWar, DeTankZone, and TankWarsZone) which is dispersed to targets by way of email or messaging platforms, whilst lending a layer of legitimacy by setting up fake web sites and accounts on X (previously Twitter).

“Moonstone Sleet usually approaches its targets through messaging platforms or by email, presenting by itself as a game developer seeking expense or developer support and either masquerading as a legit blockchain organization or making use of bogus businesses,” Microsoft researchers explained.

“Moonstone Sleet utilised a bogus organization referred to as C.C. Waterfall to speak to targets. The email introduced the activity as a blockchain-associated project and offered the concentrate on the option to collaborate, with a url to obtain the recreation bundled in the entire body of the message.”

The purported sport (“delfi-tank-unity.exe”) comes equipped with a malware loader referred to as YouieLoad, which is able of loading future-stage payloads in memory and making malicious companies for network and person discovery and browser data assortment.

A further non-existent enterprise – finish with a tailor made domain, phony staff personas, and social media accounts – produced by Moonstone Sleet for its social engineering strategies is StarGlow Ventures, which masqueraded as a legitimate program progress organization to arrive at out to possible targets for collaboration on initiatives related to web applications, mobile apps, blockchain, and AI.

Though the stop of this marketing campaign, which took place from January to April 2024, is unclear, the reality that the email messages arrived embedded with a tracking pixel raises the chance that it may possibly have been applied as part of a have confidence in-building training and establish which of the recipients engaged with the e-mail for future income generation options.

The newest software in the adversary’s arsenal is a custom made ransomware variant referred to as FakePenny that it has been located deployed against an unnamed protection technology business in April 2024 in trade for a $6.6 million ransom in Bitcoin.

The use of ransomware is a further tactic pulled straight out of Andariel’s (aka Onyx Sleet) playbook, a sub-group running in just the Lazarus umbrella acknowledged for ransomware households like H0lyGh0st and Maui.

In addition to adopting important security steps to defend from attacks by the menace actor, Redmond is urging software package organizations to be on the lookout for supply chain attacks, offered North Korean threat actors’ propensity for poisoning the software package supply chain to perform popular malicious operations.

“Moonstone Sleet’s various set of tactics is noteworthy not only simply because of their success, but mainly because of how they have developed from these of various other North Korean risk actors over quite a few several years of exercise to fulfill North Korean cyber aims,” the business explained.

The disclosure will come as South Korea accused its northern counterpart, particularly the Lazarus Team, of stealing 1,014 gigabytes of data and paperwork these kinds of as names, resident registration quantities, and fiscal data from a court network from January 7, 2021, to February 9, 2023, Korea JoongAng Every day documented earlier this month.

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Some sections of this article are sourced from:
thehackernews.com