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APT

ScarCruft and RokRAT Pose High Threat to Government and Academia

Cybersec Sentinel

• 16 min read
ScarCruft and RokRAT Pose High Threat to Government and Academia

Threat Group: ScarCruft / APT37 / Reaper / Red Eyes
Threat Type: Advanced Persistent Threat (APT), Remote‑Access Trojan (RAT), Espionage and Ransomware
Exploited Vulnerabilities: CVE‑2017‑8291 (Encapsulated PostScript vulnerability in Hangul Word Processor), CVE‑2024‑38178 (Internet Explorer mode of Microsoft Edge), vulnerabilities in Hancom Office; exploitation of Windows LNK files, DLL side‑loading and PowerShell for execution.
Malware Used: RokRAT (RokRat), LightPeek, FadeStealer, NubSpy, VCD ransomware, Chinotto, Konni RAT, Map2RAT, BLUELIGHT, GOLDBACKDOOR, Dolphin, RambleOn (Android variant), CloudMensis (macOS variant)
Threat Score: High 8.2/10 (🔴) – ScarCruft’s campaigns are advanced and targeted. They combine spear‑phishing with zero‑day exploits to deploy remote‑access trojans capable of data exfiltration and command execution. Recent campaigns show a shift toward ransomware (VCD), indicating expanding motives. The threat requires full incident response and cross‑team coordination to mitigate effectively.
Last Threat Observation: September 2 2025

Overview

What is RokRAT?

RokRAT (also spelled RokRat or Rokrat) is a sophisticated remote‑access Trojan attributed to the North Korean threat actor ScarCruft (APT37). First publicly reported in April 2017 by Cisco Talos, RokRAT is a custom malware family designed for espionage. It allows attackers to remotely control infected systems, collect sensitive information, capture screenshots, record audio, and deploy additional payloads. Early versions communicated via Twitter, Yandex and Mediafire to evade detection; modern variants use cloud services such as Dropbox, pCloud, Yandex Cloud and Google Cloud. RokRAT operates primarily on Windows but has been adapted for macOS (CloudMensis) and Android (RambleOn/Cumulus).

Who is ScarCruft?

ScarCruft (also referred to as Reaper, APT37, Inky Squid or Red Eyes) is a North Korean state‑sponsored advanced persistent threat (APT) group active since at least 2012. The group conducts cyber‑espionage campaigns against government agencies, defense contractors, journalists, human rights activists and critical infrastructure, primarily in South Korea but also in Japan, Vietnam, India, Nepal, China, Russia, Kuwait, Vietnam and Romania. ScarCruft is believed to operate under the Ministry of State Security. Its operations align with North Korea’s strategic objectives: gathering military, diplomatic and economic intelligence, suppressing dissent and generating revenue through financially motivated attacks. The group uses a diverse toolkit, including custom malware (RokRAT, Konni RAT, Chinotto, GOLDBACKDOOR, BLUELIGHT, Map2RAT, Dolphin) and commodity malware (Amadey).

Recent Evolution and Impact

ScarCruft’s campaigns have evolved significantly over the last decade. Early attacks used malicious Hangul Word Processor documents exploiting the EPS vulnerability CVE‑2017‑8291 to deliver RokRAT. The attack chain leverages a vulnerable EPS module in the HWP document; when opened, it executes shellcode that downloads a JPEG image from the attacker’s server and decrypts a hidden PE file within the image using a 16‑byte XOR key—a steganography technique—to execute RokRAT. Microsoft’s decision in 2022 to block Office macros from untrusted sources forced attackers to adopt alternative techniques; the group responded by embedding multi‑stage payloads within Windows shortcut (LNK) files. In 2024 and 2025, ScarCruft began exploiting browser vulnerabilities (CVE‑2024‑38178), malvertising campaigns (“Operation Code on Toast”) and phishing lures referencing current events (e.g., Kim Yo Jong statements, postal code updates) to target a broader range of victims.

More alarming is ScarCruft’s recent deployment of VCD ransomware. According to S2W’s August 2025 report, a ScarCruft subgroup called ChinopuNK used phishing emails with malicious archives to deliver multiple malware families (LightPeek, FadeStealer, NubSpy) and encrypt files using VCD ransomware. The ransomware appends a .vcd extension to encrypted files and leaves bilingual ransom notes (English and Korean) to demand payment. This marks a shift from espionage toward financially motivated disruption, suggesting the group is diversifying its objectives or collaborating with financially motivated actors.

Why Does It Matter?

RokRAT’s ability to surreptitiously collect data, execute commands, and leverage cloud‑based infrastructure for C2 communications makes it a formidable tool for long‑term surveillance and information theft. ScarCruft’s campaigns often focus on sensitive political, military and economic information. For organizations in government, academia, research, media and critical infrastructure, a RokRAT infection could lead to confidential data exposure, reputational damage and compliance violations. The threat score for RokRAT and ScarCruft is assessed as high (8.2/10) due to the actor’s state backing, technical sophistication and evolving tactics that now include ransomware.

Key Details

Delivery Method

  1. Spear‑phishing emails – The primary infection vector. Emails typically reference current events or targeted interests (e.g., newsletter issues, think‑tank reports, human rights discussions, postal code updates). Attachments include ZIP archives containing malicious Windows shortcut (LNK) files or Hangul Word Processor (HWP/HWPX) documents.Weaponised HWP documents and DLL side‑loading – Newer campaigns distribute malicious HWP documents that embed OLE objects. When recipients click an embedded hyperlink, Hangul automatically creates a legitimate ShellRunas.exe and a malicious credui.dll in the %TEMP% folder; executing the trusted program triggers DLL side‑loading and downloads a JPEG containing shellcode to load RokRAT.
  2. Malvertising and supply‑chain abuse – In Operation Code on Toast (2024), ScarCruft exploited a vulnerability in a Korean application used for toast advertisements to distribute malicious code through compromised ad servers.
  3. Zero‑day and n‑day vulnerability exploitation – ScarCruft has exploited CVE‑2017‑8291 in HWP documents and CVE‑2024‑38178 in Internet Explorer mode of Microsoft Edge. The group also abuses vulnerabilities in Hancom Office and uses novel infection chains—including DLL side‑loading via legitimate executables like ShellRunas.exe and steganography to hide malicious code—to bypass Microsoft’s macro security.
  4. Cross‑platform targeting – ScarCruft has developed Rokrat variants for Windows, macOS (CloudMensis) and Android (RambleOn/Cumulus), enabling them to target a range of devices and operating systems.

Target

ScarCruft primarily targets:

  • Government agencies and military organizations in South Korea and allied nations (e.g., NPO Mash in Russia). The aim is to collect strategic intelligence on defense, diplomacy and technology..
  • Academics, researchers and think tanks focused on North Korean affairs. Recent phishing lures included newsletters from the National Intelligence Research Association and decoy documents about human rights.
  • Journalists and media organizations that report on North Korea. Phishing emails impersonated members of the North Korea Research Institute and targeted individuals writing about North Korean human rights.
  • Private sector and critical infrastructure in Japan, Vietnam, India, Nepal, Russia, Kuwait and other countries. The group’s cross‑platform capabilities and new ransomware tool show potential interest in monetary gain.
  • Threat‑intelligence professionals and cyber policy organizations – SentinelOne researchers observed ScarCruft experimenting with decoy malware that impersonates threat research reports, suggesting an intent to infiltrate consumers of technical threat intelligence, including cybersecurity professionals and policy think‑tanks. By targeting those who study their activities, the adversaries aim to glean non‑public defense strategies and refine their TTPs.

Functions

RokRAT’s capabilities include:

  1. Host Profiling & Reconnaissance – Upon execution, RokRAT collects comprehensive system information: OS version, computer name, logged‑in user, BIOS data, hardware details, uptime, and the path of the executing process. It enumerates running processes and captures screenshots.
  2. Command Execution – The malware executes arbitrary commands on the host via cmd.exe or through shellcode. It can start new processes, open command shells, and perform system administration tasks.
  3. Data Exfiltration – RokRAT can collect and upload files (documents, spreadsheets, audio recordings) to the C2 servers. It includes commands to enumerate drives, scan directories, and exfiltrate selected files.
  4. Persistence & Lateral Movement – While specifics vary by campaign, RokRAT often achieves persistence by injecting into legitimate processes and creating registry run keys. In some cases, it may drop additional payloads (e.g., Map2RAT, GOLDBACKDOOR) to broaden functionality.
  5. Modular C2 Communication – The malware uses a modular approach to C2 communications, switching between local machine, Dropbox, pCloud and Yandex Cloud based on configuration. This modularity allows redundant communications and fallback options.
  6. Cloud Token Management – RokRAT stores OAuth tokens within its code and uses legitimate cloud APIs to upload and download data. It labels exfiltrated data as MP3 files to avoid suspicion.
  7. Obfuscation and Anti‑analysis – Rokrat employs encrypted strings, environment checks (e.g., verifying OS version, checking for virtualization tools and debugging processes), and dynamic code loading to hinder static and dynamic analysis. It uses hashing algorithms to hide process names and kills processes associated with analysis or previous infection vectors.

Obfuscation Techniques

  • Encrypted Strings – Both the configuration and command strings are encrypted using custom routines; this prevents easy string extraction and detection.
  • Dynamic Function Resolution – RokRAT dynamically resolves Windows API functions at runtime to avoid static signatures.
  • Environment Checks – The malware verifies the Windows version (refusing to run on Windows XP) and checks for virtualization tools (VMware tools), debugging processes (OllyDBG) and sandbox indicators (e.g., Python processes used by Cuckoo sandbox).
  • Process Injection – To evade detection, RokRAT injects its payload into legitimate processes like powershell.exe or notepad.exe.
  • Cloud C2 Disguise – Using well‑known cloud services (Dropbox, pCloud, Yandex Cloud, Google Cloud) for C2 makes network traffic appear legitimate.

Attack Vectors

RokRAT and ScarCruft campaigns combine multiple techniques to deliver malware and maintain stealth. This section details observed attack vectors based on recent research.

1. Spear‑Phishing Lures

Customized Emails – ScarCruft crafts email messages that appeal to the recipient’s interests. For example, the Operation HanKook Phantom campaign targeted academics and government officials associated with the National Intelligence Research Association. The email subject referenced “Issue 52” of the association’s newsletter, and the content urged recipients to open an attached ZIP file. Another lure used a statement from Kim Yo Jong dated 28 July 2025 to feign legitimacy.

Malicious Attachments – The attached ZIP archives contain malicious LNK files disguised as PDF or HWP documents. When a user double‑clicks the LNK file, it triggers a multi‑stage PowerShell script that drops a decoy document and silently downloads Rokrat.

Persistence via Social Media – In earlier campaigns, Rokrat used Twitter as a C2 channel; phishing emails impersonated legitimate organizations (e.g., Yonsei University) to lure victims.

2. LNK‑Based Multi‑Stage Infection Chains

Oversized LNK Files – ScarCruft’s LNK files exceed 48 MB to evade size‑based detection. Each file contains a decoy document (HWP/HWPX format), a batch script and a PowerShell script. The LNK file locates itself based on file size and extracts these components to the %Public% folder.

Decoy Documents – The HWP/HWPX document is presented to the victim to mask malicious activity. It may contain legitimate content (e.g., research papers, newsletters) to avoid suspicion. The decoy documents are sometimes stripped of metadata to hinder forensic tracing, though some contain clues like the pseudonym “bandi,” hinting at ties to the Kimsuky group.

PowerShell Execution – The extracted batch script executes the PowerShell script, which further decodes and runs another hex‑encoded PowerShell payload. This payload downloads an encrypted archive (often named myprofile.zip) from cloud storage, decrypts it using a single‑byte XOR key and executes the resulting shellcode to deploy Rokrat.

Cloud C2 Download – The PowerShell script retrieves the final payload from cloud services such as pCloud or Yandex Cloud. This approach bypasses network filters and uses TLS‑encrypted traffic to hide malicious activity.

3. Exploitation of Vulnerabilities

CVE‑2017‑8291 – The initial RokRAT campaigns exploited the Encapsulated PostScript (EPS) vulnerability in Hangul Word Processor (HWP) (CVE‑2017‑8291). Malicious HWP documents included a vulnerable EPS file that executed shellcode upon opening. The shellcode downloaded a JPEG from the attacker’s server and decrypted an embedded PE file hidden within the image using a 16‑byte XOR key—a steganography technique—before executing it.

CVE‑2024‑38178 – In Operation Code on Toast (August 2024), ScarCruft exploited a remote code execution vulnerability in the Internet Explorer mode of Microsoft Edge. A malicious URL triggered the vulnerability, enabling the group to install RokRAT. Microsoft patched the flaw during the August 2024 Patch Tuesday.

Hancom Office Vulnerabilities – Multi‑stage infection chains often abuse vulnerabilities in Hancom Office. Rokrat sometimes includes a thread (KillCertainProcessesThread) that kills processes associated with Hancom (gbb.exe and gswin32c.exe) to clean traces of exploitation.

4. Alternative Infection Vectors and Tools

Malvertising – ScarCruft has used compromised advertisement servers to deliver malicious code. The Operation Code on Toast campaign exploited a vulnerability in a Korean application, distributing malware through Toast advertisements.

Ransomware Deployment – In 2025, ScarCruft’s ChinopuNK subgroup delivered VCD ransomware via phishing emails disguised as postal code updates. This ransomware appends a .vcd extension to encrypted files and drops two ransom notes, one in English and the other in Korean. The campaign also delivered information stealers (LightPeek, FadeStealer) and the NubSpy backdoor, using PubNub for C2 communications.

Commodity Malware – ScarCruft sometimes uses publicly available malware (e.g., Amadey) to obscure attribution or as secondary payloads.

DLL Side‑Loading via HWP documents – A July 2025 AhnLab analysis uncovered a refined infection chain using Hangul Word Processor files. The malicious document embeds a hyperlink to a benign‑looking OLE object. When clicked, the Hangul application automatically extracts two files into the %TEMP% directory: a legitimate Microsoft‑signed executable (ShellRunas.exe) and a malicious dynamic link library (credui.dll). The victim is prompted to run ShellRunas.exe; because the malicious DLL resides in the same directory, it is loaded via the DLL side‑loading technique and executes. The malware then downloads a JPEG (Father.jpg) from Dropbox that contains shellcode to decode and load RokRAT into memory.

Cross‑platform variants – ScarCruft maintains malware across multiple platforms. The macOS backdoor CloudMensis is a two‑stage spyware: its second stage collects documents, screenshots, email attachments and other sensitive data from compromised Macs and exfiltrates them via public cloud services such as pCloud, Yandex Disk and Dropbox. It bypasses Apple’s Transparency, Consent and Control (TCC) protections by creating a rogue TCC database or exploiting CVE‑2020‑9934. The malware’s configuration lists file extensions of interest—including Hangul file formats (.hwp and .hwpx). On mobile, APT37 has deployed Android spyware families like KoSpy (also known as RambleOn or Cumulus); these fake utility apps obtain a configuration from Firebase and load plugins that can collect SMS messages, call logs, device location, audio recordings and screen captures. The data is encrypted and exfiltrated to cloud C2 infrastructure, allowing the group to monitor victims across devices.

Known Indicators of Compromise (IoCs)

The IoCs below are a compilation from various ScarCruft campaigns. Security teams should adapt queries for their specific logging systems and threat‑intelligence feeds.

File Hashes (MD5)

  • e11bb2478930d0b5f6c473464f2a2b6e – RokRAT binary associated with Operation Code on Toast
  • bd2d599ab51f9068d8c8eccadaca103d – RokRAT binary associated with Operation Code on Toast
  • 9a17d9b44af34aca4e94242c54e001d761993763 – RokRAT sample (SHA‑1) from Operation Code on Toast
  • a2ee8d2aa9f79551eb5dd8f9610ad557 – Malicious credui.dll used in the HWP ShellRunas side‑loading chain
  • d5fe744b9623a0cc7f0ef6464c5530da – Additional MD5 associated with RokRAT ShellRunas infection
  • e13c3a38ca58fb0fa9da753e857dd3d5 – Additional MD5 associated with RokRAT ShellRunas infection
  • e4813c34fe2327de1a94c51e630213d1 – Additional MD5 associated with RokRAT ShellRunas infection

File Hashes (SHA1)

  • 9a17d9b44af34aca4e94242c54e001d761993763 – RokRAT sample (Operation Code on Toast)
  • f0891b2fd83037f982acfaac17dcd77b091534db – RokRAT sample (Operation Code on Toast)
  • d9ac0cc6d7bdc24f52878d3d5ac07696940062d0 – myprofile.zip payload file extracted during the LNK‑based infection chain
  • e46907cfaf96d2fde8da8a0281e4e16958a968ed – Malicious Office document used as a decoy in ScarCruft phishing campaigns
  • e9df1f28cfbc831b89a404816a0242ead5bb142c – Malicious HWP document used as a decoy in ScarCruft phishing campaigns

File Hashes (SHA256)

  • 736092b71a9686fde43d3c4abd941a6774721b90b17d946c9d05af19c84df0a4 – RokRAT binary (Operation Code on Toast)
  • 95a19bb2cc53c2ff2edff89161acb9c50ea450fa8a53bbddde2ca3007b1a1345 – RokRAT binary (Operation Code on Toast)

Domains and IP Addresses

  • nav.offlinedocument[.]site – Used in multi‑stage phishing campaign (Dec 2023)
  • documentoffice[.]club – C2 infrastructure hosting decoy documents
  • one.bandi[.]tokyo – Domain connected to decoy document metadata (pseudonym “bandi”)
  • offlinedocument[.]site and documentoffice.club – Additional C2 endpoints (source: SentinelOne)
  • dailyN~1 domain references (dallynk.com) used in ScarCruft infrastructure (source: SentinelOne)
  • app.documentoffice[.]club – Subdomain used as a command‑and‑control server for malicious Office and HWP documents

URLs

  • http://discgolfglow[.]com:/wp-content/plugins/maintenance/images/worker.jpg – Malicious file downloaded during early campaigns exploiting the HWP EPS vulnerability (CVE‑2017‑8291)
  • http://acddesigns[.]com[.]au/clients/ACPRCM/kingstone.jpg – Another malicious payload host used in early RokRAT campaign
  • URLs to pCloud and Yandex Cloud for command exchange (https://api.pcloud.com/... etc.) – Observed in modern campaigns (source: SentinelOne, Check Point)

Lures and Document Names

  • “National Intelligence Research Society Newsletter – Issue 52” – Lure document used in Operation HanKook Phantom
  • Kim Yo Jong statement (dated 28 July 2025) – Lure document disguised as a political statement
  • “North Korean Human Rights Act implementation plan” – LNK file disguised as HWP document with Korean names (e.g., 3. 이윤식 북한인권법 실행방안 북한인권재단 출범 중심.lnk)
  • “Shipbuilding market price analysis (Hoeryeong)” and “Shipbuilding market price analysis (Sinuiju)” – HWP documents used in November 2023 phishing campaign

Notes on IoCs

  • These hashes and domains represent a snapshot of current campaigns. ScarCruft regularly rotates infrastructure and modifies payloads, so defenders should subscribe to threat‑intelligence feeds for updates.
  • Some campaigns employ PubNub as a command‑and‑control channel. Because PubNub is a legitimate real‑time messaging platform, defenders should monitor unusual volumes of outbound connections to PubNub endpoints and correlate them with other indicators.
  • Custom queries may be needed for specific SIEM or log formats (e.g., Splunk, Elasticsearch). For example, security teams can search for .lnk files with sizes over 40 MB or PowerShell commands downloading from cloud services.

Mitigation and Prevention

Effective defense against RokRAT and ScarCruft requires a multi‑layered approach combining user education, technical controls, patch management, network segmentation and incident response planning. The following recommendations are organized for administrators and security staff.

User Awareness

  • Phishing training – Conduct regular security awareness sessions on phishing. Use simulated phishing exercises with realistic lures (e.g., newsletters, policy statements) to train users to identify suspicious emails and attachments.
  • Attachment caution – Train employees never to open unsolicited ZIP files, LNK shortcuts or HWP documents. Encourage them to verify senders via independent channels.
  • Clear reporting mechanisms – Provide simple ways (e.g., email addresses or ticketing systems) for staff to report suspicious messages or attachments. Early reporting reduces dwell time and impact.

Email Filtering

  • Attachment scanning – Configure email gateways to block or quarantine emails containing executable content (e.g., .lnk files inside ZIP archives) or unusual macros. Use content disarm and reconstruction (CDR) to sanitize attachments. Inspect Hangul document attachments for embedded OLE objects and unusually large sizes; the ShellRunas side‑loading chain relies on legitimate executables and DLLs hidden within HWP files. Consider scanning downloaded images for hidden code or suspicious metadata, since ScarCruft has used steganography to hide shellcode within JPEG files.
  • URL reputation – Implement link scanning that checks URLs against threat‑intelligence services. Block access to domains known to host malware or command‑and‑control infrastructure (see Section 4).
  • Sender validation – Enforce SPF, DKIM and DMARC policies to reduce spoofed emails. Many ScarCruft emails impersonate legitimate organizations; strict DMARC enforcement helps detect spoofed domains.

Antivirus and Endpoint Protection

  • Endpoint detection and response (EDR) – Deploy an EDR solution that monitors file system changes, process spawning, script execution and network connections. Ensure the EDR solution is configured to detect suspicious PowerShell activity and process injection.
  • Behavioral detection – Since RokRAT uses encryption and legitimate cloud services, signature‑based detection alone is insufficient. Use behavioral heuristics to detect unusual command‑line usage (e.g., powershell.exe or cmd.exe spawned by document readers), oversized LNK files executing multi‑stage scripts, and legitimate executables loading unexpected DLLs from temporary directories. Monitor for high‑volume cloud uploads (pCloud, Dropbox, Yandex Disk, PubNub) and image downloads followed by process injections—a hallmark of ScarCruft’s steganographic payloads.
  • Application whitelisting – Restrict execution of untrusted PowerShell scripts and block running of external scripts from the %Public% or %Temp% directories.

Two‑Factor Authentication (2FA)

  • MFA for email and remote access – Require multi‑factor authentication for all remote access services, VPNs and cloud accounts. Many ScarCruft campaigns involve credential harvesting; MFA greatly reduces the risk of account takeover.
  • Privileged account protection – Use hardware security keys or FIDO2 tokens for administrative accounts to defend against phishing and credential stuffing.

Monitor Logs

  • PowerShell logs – Enable advanced PowerShell logging (ModuleLogging, ScriptBlockLogging and Transcription) to capture script execution. Centralize logs for correlation and set alerts on suspicious commands (e.g., iex or Invoke-WebRequest downloading from cloud storage).
  • Windows event logs – Monitor event IDs related to process creation, registry modifications and scheduled tasks. Rokrat often modifies run keys or schedules tasks for persistence.
  • Network and proxy logs – Inspect outbound connections for unusual patterns, such as large numbers of requests to Dropbox, pCloud, Yandex Cloud or unknown domains. Use data loss prevention (DLP) to alert on exfiltration of sensitive data.
  • Cloud access logs – If your organization uses cloud storage, implement a Cloud Access Security Broker (CASB) to monitor usage. Detect unsanctioned access or token abuse.

Regular Updates

  • Patch vulnerabilities – Apply security patches promptly. Prioritize fixing vulnerabilities exploited by ScarCruft: CVE‑2017‑8291 in HWP, CVE‑2024‑38178 in Edge’s IE mode, and known Hancom Office vulnerabilities. Patch or disable older HWP versions that still support the vulnerable EPS module.
  • Update third‑party software – Keep browser plugins, document readers and productivity suites up to date. Limit or disable outdated software prone to exploitation (e.g., older HWP versions, Internet Explorer).
  • Disable unnecessary services – Disable features like Windows Script Host (WSH) or macros if not required. The fewer avenues available for script execution, the smaller the attack surface.

Network Segmentation and Hardening

  • Segment sensitive networks – Isolate critical systems (e.g., research networks, financial systems) behind firewalls or VLANs. Use zero‑trust principles to control lateral movement.
  • Restrict outbound traffic – Implement egress filtering on firewalls to block connections to suspicious domains or cloud services seldom used by your organization.
  • Use DNS filtering – Block known malicious domains and sinkhole traffic to monitor attempted communications with C2 servers.

Incident Response Preparedness

  • Develop an IR plan – Ensure the organization has a documented and tested incident response plan for malware and ransomware incidents. Include procedures for isolating hosts, notifying stakeholders and engaging third‑party responders.
  • Backup strategy – Perform regular, offline backups of critical data. Test backups to ensure they can be restored quickly. Offline backups are the most reliable defense against ransomware (e.g., VCD).
  • Threat hunting – Conduct regular threat‑hunting exercises to detect stealthy persistence mechanisms, unusual scheduled tasks or registry modifications consistent with Rokrat or other ScarCruft tools.
  • Information sharing – Participate in information sharing with industry peers, sector‑based ISACs and national CSIRTs to receive timely threat intelligence and IoCs.

Risk Assessment

Threat Level & Scoring

Using the threat scoring guidelines provided by Cybersec Sentinel (0–10), RokRAT and ScarCruft collectively score 8.2/10, placing them firmly in the high (🔴) risk category:

  • Exploitation of multiple vulnerabilities – ScarCruft uses both known (CVE‑2017‑8291) and zero‑day vulnerabilities (CVE‑2024‑38178), along with LNK file abuses, DLL side‑loading and PowerShell exploitation. These techniques allow remote code execution with minimal user interaction, raising the threat level.
  • Advanced C2 strategies – Use of legitimate cloud services (Dropbox, pCloud, Yandex Cloud) for C2 communications, and fallback tokens for redundancy, makes detection challenging.
  • Espionage and financial motives – Historically espionage‑focused, the group now deploys ransomware, broadening the potential impact and indicating increased aggressiveness.
  • Cross‑platform support – Variants for Windows, macOS and Android expand the attack surface.
  • State backing – North Korea’s backing provides resources and persistence. The group shows adaptability and dedication to long‑term campaigns.

Potential Impact

  • Data breach and espionage – Sensitive diplomatic, military, academic and research data could be stolen and used for foreign policy advantage. Data exfiltration may also include personal information on dissidents, leading to physical harm or repression.
  • Operational disruption – Malware can disable security tools, kill processes and degrade system performance. Ransomware campaigns may render systems inoperable, requiring costly recovery efforts.
  • Financial loss – The cost of incident response, downtime, ransom payments and reputational damage can be substantial. ScarCruft’s newly deployed VCD ransomware demonstrates a willingness to extort victims.
  • Supply‑chain compromise – Use of malvertising and compromised advertisement servers indicates a risk of third‑party infection. Organizations using third‑party software or advertising networks may be impacted without direct targeting.
  • Compromised threat‑intelligence professionals – Recent campaigns have targeted consumers of technical threat intelligence reports. Compromising cybersecurity researchers and policy organizations could give ScarCruft access to non‑public defense strategies, enabling the adversary to refine its TTPs and remain undetected.

Likelihood of Occurrence

Given ScarCruft’s continued activity and successful targeting of multiple sectors, the likelihood of further attacks remains high. The group frequently refreshes its infrastructure and lures to evade detection. Organizations linked to Korean affairs or targeted industries should assume they may be victims and proactively strengthen defenses.

Conclusion and Recommendations

The combined threat of RokRAT and the ScarCruft threat actor represents a significant risk to organizations in government, academia, media and critical infrastructure. ScarCruft’s ability to craft convincing phishing lures, exploit zero‑day vulnerabilities and leverage legitimate cloud services for C2 communications makes detection challenging. RokRAT’s modular design provides comprehensive surveillance and data exfiltration capabilities, while recent adoption of ransomware suggests expanding motives.

Organizations should adopt a defense‑in‑depth strategy that emphasizes user education, proactive patch management, robust endpoint security, network segmentation and comprehensive incident response planning. Monitoring for new IoCs and participation in information sharing networks are essential, as ScarCruft frequently adjusts its infrastructure and payloads. By implementing the mitigation measures outlined above—particularly focusing on phishing awareness, email filtering, endpoint protection and regular backups—organizations can substantially reduce the risk of compromise and be better prepared to respond if an incident occurs.

Sources

  1. The Hacker News – ScarCruft Uses RokRAT Malware in Operation HanKook Phantom Targeting South Korean Academics
  2. HackRead – North Korea’s ScarCruft Targets Academics with RokRAT Malware
  3. SentinelOne – ScarCruft | Attackers Gather Strategic Intelligence and Target Cybersecurity Professionals
  4. SOCRadar – Threat Actor Profile: ScarCruft / APT37
  5. Check Point Research – Chain Reaction: ROKRAT’s Missing Link