Threats Tagged 'in-memory execution'

Security researchers have uncovered a sophisticated cyber espionage operation deploying two previously undocumented malware families, OctLurk and SilkLurk, targeting government and public-sector organizations across Central Asia and the Middle East. Both modular backdoors utilize victim-specific decryption mechanisms, extensive obfuscation, and in-memory execution to evade detection. The malware enables credential theft, remote access, network reconnaissance, and plugin-based expansion. Operations began in January 2025, affecting entities in Afghanistan, Kazakhstan, Kyrgyzstan, Syria, Tajikistan, and Uzbekistan. Victims include government offices, foreign affairs ministries, law enforcement agencies, healthcare providers, logistics organizations, research institutions, urban planning facilities, and educational establishments. Attackers deployed additional tools including Impacket's SecretsDump, Browser Password Decryptor, Pandora RC, Fscan, WinRAR, 7-Zip, and PlugX. A companion utility, LurkProxy, proxies a

MediumMalwareAfghanistanKazakhstanKyrgyzstan+3#octlurk#plugx#victim-specific decryption

After months of dormancy, XCSSET malware version 40 emerged in April 2026 targeting macOS developers through supply chain attacks. The malware hides in Xcode projects of legitimate applications on GitHub, spreading through infected development environments. V40 features advanced detection evasion through polymorphic payload generation, fileless persistence, and in-memory execution while weakening security mechanisms. It introduces 17 distinct modules including a Chrome hijacking backdoor via Chrome DevTools Protocol and a Telegram trojanizer. The malware employs multi-layered encryption, disables system security updates, terminates cloud telemetry, and locks XProtect signature databases. Primary targeting focuses on developers across South Asia. The infrastructure utilizes approximately 40 domains registered in Russia and India, demonstrating a geographic pivot in operations.

A sophisticated multi-stage malware campaign targets victims through tax-themed phishing emails impersonating Indian and Japanese government authorities. The operation leverages social engineering, fraudulent tax notifications, and trusted third-party email delivery services to distribute ZIP archives containing three staged payloads. The malware implements advanced evasion techniques including DLL Search Order Hijacking, API hooking, token manipulation, Mersenne Twister-based execution logic, COM callback execution, mutated RC4 encryption, and reflective PE loading. Execution occurs primarily in memory, significantly reducing forensic artifacts. The malware establishes persistent WebSocket-based command-and-control communication through HTTP protocol upgrades, allowing malicious traffic to blend with legitimate activity. Chinese-language artifacts were observed throughout the infrastructure and code, though attribution remains at moderate confidence. The campaign demonstrates characteristics of a mature, ...

MediumCampaignBritish Indian Ocean TerritoryIndiaJapan#websocket c2#dll hijacking#government impersonation

DesckVB RAT emerged in February 2026 through a sophisticated malspam campaign utilizing a dynamic delivery kit that personalizes lures on-the-fly by extracting victim email addresses and pulling company logos in real-time. The attack chain routes through Google's DoubleClick domain to evade email gateways before delivering a five-stage infection: HTML redirect, JScript loader, PowerShell dropper, .NET loader, and finally the RAT itself. The malware employs extensive anti-analysis techniques including sandbox detection, forced reboots upon detection, and in-memory execution via .NET reflection. Once established, it patches AMSI and ETW at the native API level, injects into legitimate Microsoft-signed binaries like InstallUtil.exe and MSBuild.exe, and establishes persistence through registry keys and scheduled tasks. The RAT communicates with DDNS-based C2 infrastructure on non-standard ports, performs system reconnaissance including GPU enumeration possibly for crypto mining, and can deliver additional payl...

Analysts discovered a new Remcos RAT infection chain starting with a batch file executing encoded commands that creates hidden directories and retrieves encrypted payloads. Unlike earlier campaigns relying on PowerShell-hosted .NET loaders, this variant incorporates DonutLoader shellcode and AutoIt-based staging for in-memory payload delivery. The infection begins with a phishing email containing a malicious batch file named Bestellung.CMD. The chain abuses legitimate Windows utilities including cscript.exe and SyncAppvPublishingServer.vbs to execute Base64-encoded payloads. Additional components are downloaded from cloud storage, including 7Zip tools and password-protected archives containing obfuscated JScript. The final payload consists of DonutLoader shellcode that injects Remcos RAT version 7.2.1 Pro into colorcpl.exe, enabling remote control, credential harvesting, keystroke logging, and additional payload deployment.

A sophisticated spear-phishing campaign designated Operation Dragon Whistle has been identified targeting Changzhou University in China. The threat actor UNG002 leveraged highly contextual social engineering by impersonating official university communications regarding mandatory 2026 National Student Physical Fitness and Health Standards testing, which directly impacts graduation eligibility. The attack chain begins with a weaponized ZIP file containing a malicious LNK file disguised as a PDF document. Upon execution, it triggers a VBScript that simultaneously displays a legitimate-looking decoy document while deploying a multi-stage infection chain involving DLL sideloading via Bandizip.exe, anti-debugging techniques, and ultimately delivering a Cobalt Strike Beacon payload entirely in memory. The campaign demonstrates advanced evasion capabilities and utilizes Chinese cloud infrastructure hosted on Alibaba Cloud for command and control operations.

MediumMalwareChina#spear-phishing#dll sideloading#in-memory execution

In late February 2026, following escalating Middle East tensions and coordinated military actions, Iranian APT group Seedworm launched sophisticated social engineering attacks via Microsoft Teams. Attackers impersonated IT support personnel using deceptive Microsoft 365 tenant domains to convince victims to execute malicious MSI installers. The campaign deployed a custom backdoor called Dindoor, which leveraged legitimate Deno runtime to execute obfuscated payloads in-memory, minimizing detection. The operation included multiple components for persistence, command-and-control communications, and data exfiltration. Infrastructure overlapped with previously reported MuddyWater operations. The attack demonstrates the group's evolution in using collaboration platforms as initial access vectors while combining dual-use tooling with living-off-the-land techniques to bypass traditional security controls.

In February 2026, an attack chain was discovered that utilized a fraudulent Adobe Acrobat Reader download page to deceive victims into installing ConnectWise's ScreenConnect, a legitimate remote access tool exploited for malicious purposes. The attack employs sophisticated evasion techniques including heavy obfuscation, .NET reflection for in-memory payload execution, and dynamic code construction. A VBScript loader initiates the chain by downloading and executing obfuscated PowerShell commands that compile C# code entirely in memory. The loader manipulates the Process Environment Block to masquerade as legitimate Windows processes and abuses auto-elevated COM objects to bypass User Account Control without user prompts. This multi-layered approach successfully evades signature-based defenses and hinders forensic analysis while ultimately deploying ScreenConnect for unauthorized remote access.

Operation DualScript is a sophisticated multi-stage malware campaign targeting cryptocurrency and financial activities. It utilizes Windows Scheduled Tasks, VBScript launchers, and PowerShell execution to maintain persistence while minimizing disk artifacts. The attack operates through two parallel chains: a web-based PowerShell loader deploying a cryptocurrency clipboard hijacker, and a secondary chain executing the RetroRAT implant in memory. RetroRAT monitors user activity, captures keystrokes, and tracks interactions with financial services to harvest sensitive information. The malware employs various anti-analysis techniques and establishes a command-and-control channel for remote access and data exfiltration. This campaign highlights the growing abuse of trusted system utilities and in-memory execution techniques to evade traditional detection mechanisms.

MediumMalwareUnited StatesRussiaChina+7#cryptocurrency#retrorat#multi-stage

LeakNet, a ransomware operator, has expanded its initial access methods by utilizing ClickFix lures on compromised websites and implementing a new Deno-based, in-memory loader. The group has shifted from relying on initial access brokers to running its own campaigns. LeakNet's post-exploitation playbook remains consistent, involving jli.dll side-loading, PsExec-based lateral movement, and S3 bucket payload staging. The Deno loader executes base64-encoded payloads in memory, making detection challenging for traditional security tools. Defenders are advised to focus on behavioral signals and implement measures such as blocking newly registered domains, restricting Win-R access, and limiting PsExec usage to authorized administrators.

MediumCampaignUnited StatesUnited KingdomGermany+7#side-loading#s3 bucket#lateral movement