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August 22, 2024

From the Depths: Analyzing the Cthulhu Stealer Malware for macOS

Cado Security (now part of Darktrace) analyzed "Cthulhu Stealer," a macOS malware-as-a-service written in Go. It impersonates legitimate software, prompts for user and MetaMask passwords, and steals credentials, cryptocurrency wallets, and game accounts. Functionally similar to Atomic Stealer, Cthulhu was rented via an underground marketplace, but its operators faced complaints and a ban for alleged exit scamming.
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Tara Gould
Malware Research Lead
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Aug 2024

Introduction

For years there has been a general belief that macOS systems are immune to malware. While MacOS has a reputation for being secure, macOS malware has been trending up in recent years with the emergence of Silver Sparrow [1],  KeRanger [2], and Atomic Stealer [3], among others. Recently, Cado Security has identified a malware-as-a-service (MaaS) targeting macOS users named “Cthulhu Stealer”. This blog will explore the functionality of this malware and provide insight into how its operators carry out their activities.

Technical analysis

File details:

Language: Go

Not signed

Stripped

Multiarch: x86_64 and arm

Screenshot
Figure 1: Screenshot of disk image when mounted

Cthulhu Stealer is an Apple disk image (DMG) that is bundled with two binaries, depending on the architecture. The malware is written in GoLang and disguises itself as legitimate software. Once the user mounts the dmg, the user is prompted to open the software. After opening the file, “osascript”, the macOS command-line tool for running AppleScript and JavaScript is used to prompt the user for their password. 

Password Prompt
Figure 2: Password Prompt 
Osascript
Figure 3: Osascript prompting user for password

Once the user enters their password, a second prompt requests the user’s MetaMask [4] password. A directory is created in ‘/Users/Shared/NW’ with the credentials stored in textfiles. Chainbreak [5] is used to dump Keychain passwords and stores the details in “Keychain.txt”.

Wallet Connect Password prompt
Figure 4: Password prompt for MetaMask
Directory
Figure 5: Directory /Users/Shared/NW with created files

A zip file containing the stolen data is created in: “/Users/Shared/NW/[CountryCode]Cthulhu_Mac_OS_[date]_[time].zip.” Additionally, a notification is sent to the C2, to alert to new logs. The malware fingerprints the victim’s system, gathering information including IP, with IP details that are retrieved from ipinfo.io.  

System information including system name, OS version, hardware and software information is also gathered and stored in a text file.

Parsed IP Details
Figure 6: Parsed IP Details 
Cthulhu Stealer
Figure 7: Contents of ‘Userinfo.txt’
Code
Figure 8: Part of the function saving system information to text file
Log Alert
Figure 9: Alert of Log that is sent to operators

Cthulhu Stealer impersonates disk images of legitimate software that include:

  • CleanMyMac
  • Grand Theft Auto IV (appears to be a typo for VI)
  • Adobe GenP

The main functionality of Cthulhu Stealer is to steal credentials and cryptocurrency wallets from various stores, including game accounts. Shown in Figure 10, there are multiple checker functions that check in the installation folders of targeted file stores, typically in “Library/Application Support/[file store]”. A directory is created in “/Users/Shared/NW” and the contents of the installation folder are dumped into text files for each store.

Code
Figure 10: “Checker” functions being called in main function
Code
Figure 11: Function BattleNetChecker

A list of stores Cthulhu Stealer steals from is shown in the list below:

  • Browser Cookies
  • Coinbase Wallet
  • Chrome Extension Wallets
  • Telegram Tdata account information
  • Minecraft user information
  • Wasabi Wallet
  • MetaMask Wallet
  • Keychain Passwords
  • SafeStorage Passwords
  • Battlenet game, cache and log data
  • Firefox Cookies
  • Daedalus Wallet
  • Electrum Wallet
  • Atomic Wallet
  • Binanace Wallet
  • Harmony Wallet
  • Electrum Wallet
  • Enjin Wallet
  • Hoo Wallet
  • Dapper Wallet
  • Coinomi Wallet
  • Trust Wallet

Comparison to atomic stealer

Atomic Stealer [6] is an information-stealer that targets macOS written in Go that was first identified in 2023. Atomic Stealer steals crypto wallets, browser credentials, and keychain. The stealer is sold on Telegram to affiliates for $1,000 per month. The functionality and features of Cthulhu Stealer are very similar to Atomic Stealer, indicating the developer of Cthulhu Stealer probably took Atomic Stealer and modified the code. The use of “osascript”  to prompt the user for their password is similar in Atomic Stealer and Cthulhu, even including the same spelling mistakes. 

Forum and operators

The developers and affiliates of Cthulhu Stealer operate as “Cthulhu Team” using Telegram for communications. The stealer appears to be being rented out to individuals for $500 USD/month, with the main developer paying out a percentage of earnings to affiliates based on their deployment. Each affiliate of the stealer is responsible for the deployment of the malware. Cado has found Cthulhu Stealer sold on two well-known malware marketplaces which are used for communication, arbitration and advertising of the stealer, along with Telegram. The user “Cthulhu” (also known as Balaclavv), first started advertising Cthulhu Stealer at the end of 2023 and appeared to be operating for the first few months of 2024, based on timestamps from the binaries. 

Various affiliates of the stealer started lodging complaints against Cthulhu in 2024 with regards to payments not being received. Users complained that Cthulhu had stolen money that was owed to them and accused the threat actor of being a scammer or participating in an exit scam. As a result, the threat actor received a permanent ban from the marketplace.

Screenshot
Figure 12: Screenshot of an arbitration an affiliate lodged against Cthulhu

Key takeaways 

In conclusion, while macOS has long been considered a secure system, the existence of malware targeting Mac users remains an increasing security concern. Although Cthulhu Team no longer appears to be active, this serves as a reminder that Apple users are not immune to cyber threats. It’s crucial to remain vigilant and exercise caution, particularly when installing software from unofficial sources.

To protect yourself from potential threats, always download software from trusted sources, such as the Apple App Store or the official websites of reputable developers. Enable macOS’s built-in security features such as Gatekeeper, which helps prevent the installation of unverified apps. Keep your system and applications up to date with the latest security patches. Additionally, consider using reputable antivirus software to provide an extra layer of protection.

By staying informed and taking proactive steps, you can significantly reduce the risk of falling victim to Mac malware and ensure your system remains secure.

Indicators of compromise

Launch.dmg  

6483094f7784c424891644a85d5535688c8969666e16a194d397dc66779b0b12  

GTAIV_EarlyAccess_MACOS_Release.dmg  

e3f1e91de8af95cd56ec95737669c3512f90cecbc6696579ae2be349e30327a7  

AdobeGenP.dmg  

f79b7cbc653696af0dbd867c0a5d47698bcfc05f63b665ad48018d2610b7e97b  

Setup2024.dmg  

de33b7fb6f3d77101f81822c58540c87bd7323896913130268b9ce24f8c61e24  

CleanMyMac.dmg  

96f80fef3323e5bc0ce067cd7a93b9739174e29f786b09357125550a033b0288  

Network indicators  

89[.]208.103.185  

89[.]208.103.185:4000/autocheckbytes  

89[.]208.103.185:4000/notification_archive  

MITRE ATTACK  

User Execution  

T1204  

Command and Scripting Interpreter: Apple Script  

T1059.002  

Credentials From Password Stores  

T1555  

Credentials From Password Stores: Keychain  

T1555.001  

Credentials From Password Stores: Credentials From Web Browser  

T1555.003  

Account Discovery   

T1087  

System Information Discovery  

T1082  

Data Staged  

T1074  

Data From Local System  

T1005  

Exfiltration Over C2 Channel  

T1041  

Financial Theft  

Detection

Yara

rule MacoOS_CthulhuStealer {   
meta:       
 Description = "Detects Cthulhu MacOS Stealer Binary"       
 author = "Cado Security"       
 date = "14/08/2024"       
 md5 = "897384f9a792674b969388891653bb58" strings:           
 $mach_o_x86_64 = {CF FA ED FE 07 00 00 01 00 00 00 00 00 00 00 00}           
 $mach_o_arm64 = {CF FA ED FE 0C 00 00 01 00 00 00 00 00 00 00 00}          $c2 = "http://89.208.103.185:4000"           
 $path1 = "/Users/Shared/NW" fullword          $path2 = "/Users/admin/Desktop/adwans/Builder/6987368329/generated_script.go" fullword          $path3 = "ic.png" fullword           
 $zip = "@====)>>>>>>>>> CTHULHU STEALER - BOT <<<<<<<<<(====@\n" fullword          $func1 = "copyKeychainFile"           
 $func2 = "grabberA1"           
 $func3 = "grabberA2"          
 $func4 = "decodeIPInfo"           
 $func5 = "battlenetChecker"           
 $func6 = "binanceChecker"          
 $func7 = "daedalusChecker"           
 $func8 = "CCopyFFolderContents"           
 $func9 = "electrumChecker"         
 
condition:         
 $mach_o_x86_64 or $mach_o_arm64           
 and any of ($func*) or any of ($path*) or ($c2) or ($zip) } 

References

[1] https://redcanary.com/blog/threat-intelligence/clipping-silver-sparrows-wings/

[2] https://unit42.paloaltonetworks.com/new-os-x-ransomware-keranger-infected-transmission-bittorrent-client-installer/

[3] https://www.sentinelone.com/blog/atomic-stealer-threat-actor-spawns-second-variant-of-macos-malware-sold-on-telegram/

[4] https://metamask.io/

[5] https://github.com/n0fate/chainbreaker

[6] https://www.sentinelone.com/blog/atomic-stealer-threat-actor-spawns-second-variant-of-macos-malware-sold-on-telegram/

Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Tara Gould
Malware Research Lead

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June 12, 2026

Cybersecurity for the Sports Sector: The Threats Facing a Digitized Industry in 2026

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Securing sporting events in 2026

When you walk into a stadium on game day, you are entering a small smart city. Ticketing, turnstiles, payments, public Wi-Fi for tens of thousands of fans, CCTV, lighting, even the HVAC all run on connected systems. The experience for fans has become unmatched, but that dependency has created a much larger attack surface than people may realize.

Our latest threat research backs that up. In the past year, a survey that Darktrace commissioned found that 84% of respondents from professional sports organizations had at least one cyber incident, and 57% were hit more than once. For a sector that relies on the impact of the live moment, those numbers translate directly into operational risk.

Why sports is a target for cyber attacks

Sport is a highly visible target with fixed timelines, so attackers know exactly when disruption will have the most impact. It also holds valuable data, athlete medical records, contracts, sponsorship deals, which carry financial, reputational, and regulatory risk if exposed. At the same time, delivery depends on a wide set of third parties: ticketing providers, broadcasters, cloud services, stadium technology. Any of those connections can become an entry point. Put visibility, timing, data, and dependency together, and you get an environment where even a small foothold can turn into a visible, time-critical incident.

How attackers target email and identity

Email and identity remain the front door. From October 2025 through March 2026, Darktrace / EMAIL™ detected more than 116,000 phishing emails aimed at sports organizations across our customer base, and our sports customers received 19% more phishing emails than organizations in other sectors. The numbers tell the story:

BY THE NUMBERS

  • 21% of phishing emails were aimed at VIPs.
  • 37% used novel social engineering.
  • 84% of malicious emails passed DMARC authentication

A large proportion of these emails passed authentication checks, which means traditional security controls are no longer a reliable barrier. Attackers are not relying on spoofed domains – they're using legitimate infrastructure and trusted platforms. Behavior matters. Once an account is compromised, the behavior shifts quickly. Login patterns change, inbox rules are created to hide responses, and accounts start being used for internal discovery or further phishing. These aren’t high-noise events. They sit in normal workflows, which is why they’re often missed.

Ransomware tells a similar story. In one case inside a sports deployment, attackers had quietly been moving data to an outside server for a full two weeks before they triggered encryption. By the time the ransom note appeared, the outcome was already set. That sequence shows up consistently is access first, movement next, disruption last. If detection starts at encryption, it’s already too late.

Why AI is an emerging blind spot in sports

The increasing adoption of AI is expanding the potential attack surface. 72% of the security professionals we surveyed expect AI to increase their cyber risk over the next year, and yet 35% are already using or planning to use it in stadium operations, the most critical functions to protect. In addition to prompt injection and AI build risks, shadow AI is becoming a more immediate issue. Staff are already putting sensitive data—performance metrics, scouting reports, contracts, health data—into tools with little or no governance. The upside is clear, but so is the exposure—and it is happening before most organizations have any visibility or control. At the same time, attackers are using the same technology to scale phishing and social engineering. The net effect is simple: more exposure, at higher speed.

How can cybersecurity professionals prepare

Across high profile events, Darktrace’s experience shows that effective cyber defense includes preparation, real‑time visibility, and the ability to respond dynamically and decisively when timing, complexity, and public exposure converge.

There are a few strategic implications for cybersecurity teams:

  • Get behavioral visibility across IT and OT, not just corporate systems.
  • Treat identity as your control plane. Most attacks in this sector start with credentials, not malware. MFA with behavioral detection helps solve that challenge.
  • Control third party and AI access the same way you control your own environment.
  • Rehearse response for live conditions, where decisions happen in minutes. Detection and response need to account for non-ideal conditions when engineers are under pressure and time constrained. In sport, timing is what turns small issues into major incidents. The same activity that would be manageable midweek becomes critical during a live event.

Why 2026 raises the cybersecurity stakes for sports

With the 2026 World Cup about to stretch across three countries and dozens of host cities, the attack surface is wide and the schedule is unforgiving.

Geopolitical signaling is raising the threat profile further. Previous international sporting events have demonstrated that nation‑state actors use the cyber domain to signal intent, influence narratives, or retaliate symbolically. In the context of the 2026 World Cup, Russia’s continued exclusion from international sport, the ongoing conflict in Ukraine, US defensive support to Ukraine, and Iran’s likely participation in the tournament introduce additional motivations for state‑aligned and non‑traditional affiliated actors to operate below the threshold of armed conflict. This doesn’t require new techniques—just the right timing and visibility.

In practice, this comes down to preparation: knowing what normal looks like across IT and OT, controlling third-party access, and spotting when behavior shifts.

In sport, disruption does not build slowly—it happens in real time and in public. By that point, the groundwork has already been set, long before the whistle goes.

About this research

Findings are based on Darktrace threat-research telemetry across sports-sector customer deployments (Q4 2025–Q1 2026) and a survey of 875 IT cybersecurity professionals in the US, UK, Australia, and Germany, fielded by Opinion Matters between May 28 and June 3, 2026. Read the full report for complete methodology, incident analysis, and strategic recommendations.

[related-resource]

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About the author
Nathaniel Jones
VP, Security & AI Strategy, Field CISO

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June 12, 2026

Protecting Stadiums & Events with AI

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Stadium and large public venue operators are confronted with a unique set of cyber security challenges. Often described as a ‘honeypot’ for cyber-criminals, the sports and entertainment industry is an attractive target for threat actors for three main reasons:

  • Modern sports organizations process sensitive and highly valuable data at scale;
  • Sporting events are highly visible and time-critical, operating in front of live audiences with no room for error;
  • Sports organizations rely on sprawling vendor ecosystems and supply chains to deliver broadcast, commerce, fan engagement services, and more.

In a recent Darktrace-commissioned survey, 84% of professional sports organizations reported at least one cyber incident in the past year, and 57% were hit more than once [1]. The potential ramifications of cyber disruption during a large-scale sports event cannot be overstated. A momentary lapse in access to power could bring TV broadcasts to a halt; disruption to access controls could restrict fans from entering the grounds; CCTV outages could increase the risk of criminal behavior and physical injuries. If data is not reliable and stadium machines are outputting the wrong metrics, a venue could become dangerously overcrowded. The barrier between the cyber and physical worlds has long dissolved – cyber-attacks threaten human safety.

In this blog, I explore the key challenges of stadium cyber security and explain the unique capabilities of Self-Learning AI that led me to adopt Darktrace as a head of ICT and cyber security for international venues and events. Over my career I have helped secure football and rugby World Cups, World Athletics Championships and more than 500 events ,and the lessons from each have only sharpened my conviction in this approach.

The access paradox

The biggest challenge lies in the paradox of securing a site where various internal services are provided to a large number of unknown and unmanaged users, suppliers and devices. When it’s game time, or ‘D-Day’, you see a huge influx of thousands of people, each with their own devices, needing to connect to your network and your infrastructure. The floodgates are opened. But certain parts of your digital environment need to remain protected: your sensitive employee and customer data, your critical OT systems. I liken this to opening the door to your home, and letting the entire town come in and wander around. But you still need to secure your master bedroom.

A multitude of different actors must be able to work on-site to provide services or content during the event. Broadcasters, staff and suppliers need to have access to manage the show, and all these people need to access or interact with the IT infrastructure. In many ways, these additional bodies are already inside the perimeter and could host unknown malicious threats.

This year, the paradox is wider than ever. A tournament spread across hundreds of suppliers and vendors means the foothold an attacker needs may already belong to a trusted partner – a single compromised supplier can become the doorway to everything else. And the adversary is no longer working alone: generative AI now lets attackers probe and weaponize vulnerabilities across thousands of software dependencies at a speed no human team could match, turning the access paradox from a manageable risk into a fast-moving target.

Achieving this balance between accessibility and security requires a shift in mindset from perimeter-based security to one that can detect and respond to threats on the inside. The complexities involved requires technology that can identify malicious behavior in real time based on the wider context of an incident. A particular behavior or connection may be benign in one context and yet critically disruptive in another — tools and technology must be able to discern between the two.

This is why I considered Darktrace’s Self-Learning AI a suitable fit: rather than defending at the perimeter, it focuses on detecting and responding to malicious activity already inside. Because it learns the unique ‘patterns of life’ of its surroundings, it can detect subtle deviations that indicate a threat and initiate a targeted response – without relying on pre-programmed rules and playbooks.

IT/OT convergence

The second key challenge is the issue of IT and OT convergence. Typical stadiums and arenas consist of a wide range of Industrial Control Systems (ICS).

This involves a complex and messy array of switches, cables, CCTV cameras, as well as devices and technologies being brought in by the media and the press, and all these IT and OT components are now interconnected, which means these technologies now have Internet Protocol (IP)-based threats to manage. The same challenges that the corporate infrastructure for stadium management faces in cyber security are therefore also now an issue for ICS security.

This challenge cannot be addressed by viewing IT and OT security in isolation — these two environments are linked because of the analogue migration to IP. A unified approach is required to detect and respond to threats that start in IT before moving to industrial systems.

The stakes are physical. CCTV, Access Control, Public Annoucement system, lighting and the giant screens are all now running over IP, and a disruption to any of them can force a venue to halt play on safety grounds. Scale compounds the problem. At the Qatar 2022 World Cup, eight stadiums were purpose-built to a single technical standard, which made the digital environment relatively uniform to defend. The 2026 tournament is the opposite: dozens of host venues across three countries, each with its own operator, its own contractors and its own legacy systems.This creates a far more fragmented and unpredictable estate to secure.

In addition, cyber security technology must be able to deal with complexity. Darktrace’s AI thrives in the most complex environments, with more data points adding more context to inform the AI’s decision making. It covers OT and IT with a single, unified AI engine, that can also detect and respond across cloud infrastructure, SaaS applications, email systems and endpoints. It is ready to adapt to the messy, interconnected systems that make up large stadiums’ digital infrastructure.

The time factor

Finally, the nature of stadium events means that timing is critical and puts enormous pressure on the organizers and operators. ‘D-Day’ cannot be replayed or postponed, and so if cyber disruption occurs during the event, every minute is crucial. You cannot reschedule a World Cup final or move an opening ceremony; the date is fixed, the world is watching, and there is no second take.

There is consequently a strong emphasis on two key metrics

  • Mean Time To Know (MTTK) — how long it takes the security team need to be aware of an incident; and
  • Mean Time To Restore (MTTR) — how quickly a team can act to contain the threat.

It is perhaps more imperative in stadium event management than anywhere else that these two metrics be minimized.

This leads to the third criteria in assessing cyber security technology: does it help with response? And critically, can that response be nuanced and targeted, able to contain that threat without causing further disruption?

To this end, Darktrace’s Autonomous Response takes machine-speed action to contain cyber-attacks, when humans are too slow to react or aren’t around at all. It’s powered by Darktrace’s AI, so it has a nuanced and continuously updating understanding of what’s ‘normal’ across IT and OT systems. This means its response actions are targeted: designed to eliminate the threat, but not at the cost of disruption. Crucially, this enables responses that are surgical rather than blunt. For example, taking an entire server offline to stop a ransomware attack can cause more disruption than the attack itself, so the real value lies in neutralizing the malicious activity precisely — containing the threat without taking down the systems the event and business depends on.

Depending on the nature and severity of the threat, the technology can block specific malicious connections by enforcing the normal ‘pattern of life’ of a device or account. When every second counts, this is the speed and granularity that you need in a cybersecurity technology.

Darktrace can be deployed across every area of the digital enterprise, including network, email, cloud and SaaS environments with the same self-learning approach, stopping anomalous behaviors that point to account takeover and other cloud-based threats. Earlier this year, we announced that Darktrace is also extending its behavioral approach to help businesses deploy and scale AI securely by understanding how these AI systems and agents behave, interact with other systems and humans, and evolve over time. This is critical because 72% of cybersecurity professionals at sports organizations believe AI will increase their cyber risk over the next 12 months [2].

Wherever it is deployed, Darktrace allows the stadium operator to focus on the vital part of the game and offers real-time protection without any modification in the network topology or infrastructure.

An adaptive defense

Cyber-criminals are constantly developing their approach in an attempt to evade security tools trained to look for specific hallmarks of an attack. As they get creative and continuously experiment with new tactics and techniques, the human operators using these tools are forced into a constant state of catch up.

An AI-based approach that learns an organization and its normal behavior patterns from the ground up puts an end to this game of ‘cat and mouse’, shifting the balance in favor of the defenders and allowing them to stay ahead of the threat. This matters more than ever, because adversaries are now using AI to scale their attacks. If you do not have AI working to protect you against malicious AI, you are already at a disadvantage.

With a nuanced understanding of what’s ‘normal’ for the business, unified IT/OT coverage, and an Autonomous Response solution that takes immediate, surgical action, the playing field is leveled, and large stadium and events operators can focus on delivering the best possible experience for attendees, digital viewers, partners and performers.

[related-resource]

References:

[1] [2] Darktrace: Cybersecurity in Global Sport, June 2026. Findings based on survey of 875 IT cybersecurity professionals based in the US, UK, Australia and Germany, working in professional sports organizations (including clubs, societies & sporting bodies) employing 10+ people. The survey was fielded between May 28, 2026 and June 3, 2026 by independent market research agency, Opinion Matters.

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