Threats Tagged 'lumma stealer'

ESET Research contributed to a global disruption operation targeting the Amadey botnet and Stealc infostealer, both malware-as-a-service offerings. The operation, coordinated by Microsoft Digital Crimes Unit, BitSight, Lumen, and MBSD, impacted approximately 50 domains and nearly 200 active IP-based command and control servers. ESET provided technical analyses, statistical information, C&C server lists, encryption keys, campaign identifiers, and affiliate-level insights gathered from three years of tracking. Both malware families operate through affiliate networks where operators deploy their own infrastructure, making disruption efforts particularly challenging. Amadey primarily functions as a modular loader distributing additional payloads, while Stealc focuses on credential theft from browsers, crypto wallets, and applications. The largest Amadey botnet cluster accounted for 34% of all samples and distributed an average of 14 payloads per victim, operating a pay-per-install model that monetized compromi...

Infostealers remain among the most pervasive cybercrime threats, silently harvesting passwords, cookies, and session tokens that enable enterprise breaches. StealC is a malware-as-a-service infostealer written in C++ that collects credentials from browsers, cryptocurrency wallets, messaging applications, email clients, and gaming platforms while functioning as a secondary loader. Amadey operates as a modular backdoor loader active since 2018, delivering downstream payloads including StealC, Lumma Stealer, and ransomware through various backdoor commands. Both operate on commodity rental models where stolen credentials flow through underground markets to access brokers who resell enterprise access. On June 24, 2026, Microsoft's Digital Crimes Unit coordinated with Europol to disrupt over 200 malicious command-and-control domains supporting these operations, using AI-assisted analysis tools including Microsoft Copilot for binary analysis and configuration extraction.

Threat actors are increasingly leveraging the global interest in artificial intelligence by impersonating popular AI platforms such as ChatGPT, Copilot, DeepSeek, and Claude in social engineering campaigns. These operations span phishing attacks, malvertising, and search engine optimization-driven tactics that ultimately lead to credential theft, financial fraud, or malware infections. Observed campaigns include ChatGPT-themed phishing collecting credit card data targeting South Africa, Claude-themed adversary-in-the-middle attacks harvesting credentials and access tokens, malvertising campaigns distributing Vidar stealer through fake AI plugin downloads, and fraudulent DeepSeek V4 installers on GitHub. The initial access broker Storm-3075 has been identified employing AI-themed malvertising, while the financially motivated actor Fox Tempest provides malware-signing-as-a-service to enhance payload legitimacy. These campaigns combine traditional social engineering tactics with AI branding to improve success...

Fox Tempest is a financially motivated threat actor operating a malware-signing-as-a-service (MSaaS) business used by cybercriminals to distribute malicious code, including ransomware. The actor abuses Microsoft Artifact Signing to generate fraudulent code-signing certificates, allowing malware to evade security controls. Fox Tempest created over a thousand certificates and established hundreds of Azure tenants to support operations. Microsoft revoked over one thousand certificates and disrupted the service in May 2026 through the Digital Crimes Unit. The operation enabled ransomware deployment including Rhysida by threat actors like Vanilla Tempest, and distributed malware families including Oyster, Lumma Stealer, and Vidar. The MSaaS was available through signspace[.]cloud, charging between $5000-$9000 USD. Attacks impacted healthcare, education, government, and financial services sectors globally.

A sophisticated 64-bit information-stealing malware named Remus has emerged as a direct evolution of the notorious Lumma Stealer. Following the doxxing of alleged Lumma core members between August and October 2025, developers created this advanced variant, with test builds appearing in September 2025 and live campaigns starting February 2026. Remus employs innovative techniques including injecting custom 51-byte shellcode into browser memory to extract protected master keys, bypassing Application-Bound Encryption in Chromium-based browsers. The malware utilizes EtherHiding through Ethereum smart contracts for command-and-control resolution, making infrastructure takedowns nearly impossible. It targets browser credentials, session cookies, and cryptocurrency wallets while implementing rigorous anti-analysis checks to evade security research environments.

A ClickFix-style phishing campaign leveraged social engineering to trick users into executing obfuscated PowerShell commands that downloaded and installed a malicious MSI payload from a remote server. The attack employed a sophisticated multi-stage infection chain utilizing DLL sideloading techniques with renamed legitimate binaries to execute malicious components. The final payload deployed HijackLoader to deliver a Lumma-style information stealer designed for credential harvesting and data exfiltration. The campaign utilized multiple command-and-control domains and infrastructure hosted on specific IP addresses. Mitigation measures include blocking identified artifacts, enhancing user awareness about ClickFix social engineering tactics, implementing endpoint detection for suspicious PowerShell activity and unsigned DLL sideloading, and isolating compromised systems for remediation.

Gen Threat Labs has identified Remus, a new 64-bit infostealer attributed to the Lumma Stealer family, emerging after Lumma's takedown and the doxxing of its alleged core members. First campaigns date back to February 2026, with the malware switching from Steam/Telegram dead drop resolvers to EtherHiding and employing new anti-analysis checks. Remus shares multiple characteristics with Lumma including identical string obfuscation techniques, AntiVM checks, direct syscall/sysenter handling, indirect control flow obfuscation, and a unique Application-Bound Encryption bypass. The analysis details test builds labeled Tenzor from September 2025, representing a transitional step between Lumma and Remus. While maintaining Lumma's stealing arsenal for browser passwords, cookies, and cryptocurrency, Remus introduces blockchain-based C2 resolution via EtherHiding, additional anti-sandbox checks targeting analysis tool DLLs, and enhanced device fingerprinting capabilities.

GhostSocks is an emerging threat that turns compromised devices into residential proxy nodes, enabling attackers to evade detection. Originally marketed on Russian underground forums as Malware-as-a-Service, it has gained popularity due to its partnership with Lumma Stealer. Written in GoLang, GhostSocks uses SOCKS5 proxy protocol and TLS encryption to blend malicious traffic into normal network activity. It also incorporates backdoor functionality for running arbitrary commands and deploying additional payloads. Darktrace observed an increase in GhostSocks activity, detecting it alongside Lumma Stealer in customer networks. The malware's versatility in converting devices into proxy nodes while enabling covert network access illustrates how threat actors maximize the value of compromised infrastructure.

MediumCampaignUnited StatesRussiaGermany+7#c2 infrastructure#ghostsocks#evasion techniques

Insikt Group identified five distinct clusters using the ClickFix social engineering technique for initial access. These clusters impersonate various services like Intuit QuickBooks and Booking.com, demonstrating operational variance but similar core techniques. ClickFix manipulates victims into executing malicious commands within native system tools, bypassing traditional security controls. The methodology has become a standardized template for cybercriminals and APT groups. Campaigns target diverse sectors and use sophisticated obfuscation and living-off-the-land tactics. Defenders are advised to implement aggressive behavioral hardening and user awareness training to mitigate these threats.

MediumCampaignUnited StatesUnited KingdomCanada+7#living-off-the-land#vidar#windows

A malicious campaign exploiting Google Groups to distribute Lumma Stealer and Ninja Browser malware has been uncovered. The attackers infiltrate industry-related forums, posting seemingly legitimate technical discussions with embedded malicious download links. For Windows users, the payload is Lumma Stealer, a credential-harvesting malware. Linux users are directed to download a trojanized Chromium-based browser called Ninja Browser, which installs malicious extensions and persistence mechanisms. The campaign utilizes Google's trusted ecosystem to bypass security measures and increase user confidence. Over 4,000 malicious Google Groups and 3,500 Google-hosted URLs have been identified in this global operation, posing significant risks to organizations including credential theft, account takeover, and remote command execution.

MediumMalwareGermanyFranceUnited Kingdom+5#social engineering#ninja browser#trojanized browser