fileless attacks Archives

Tech Optimizer

December 3, 2025

Fileless protection explained: Blocking the invisible threat others miss

Fileless malware operates within a computer's active memory, avoiding detection by traditional antivirus solutions that rely on file scanning. It uses legitimate tools like PowerShell to execute harmful commands without creating files, making it difficult to identify. Cybercriminals can use fileless malware for various malicious activities, including data theft and cryptocurrency mining. Malwarebytes combats fileless attacks through two defense layers: Script Monitoring, which intercepts potentially dangerous scripts at execution, and Command-Line Protection, which scrutinizes command-line tools for suspicious activities. Examples of fileless attacks include malicious email attachments activating PowerShell to download ransomware, hidden JavaScript on websites mining cryptocurrency, and attackers using Windows Management Instrumentation (WMI) to create backdoors. Malwarebytes' Fileless Protection operates automatically in the background, ensuring legitimate applications function normally while monitoring for threats. It is part of a comprehensive security framework that includes machine-learning detection and web protection, designed to stop attacks that do not write files. This protection is included with Malwarebytes Premium, aimed at safeguarding personal and small business systems.

Winsage

August 5, 2025

North Korean Cyberattackers Conceal Malicious Software Inside JPEG Images

North Korean state-sponsored hackers, part of the APT37 group, are using advanced steganography techniques to embed malicious software within JPEG image files. The RoKRAT malware variant employs a two-stage encryption process, starting with the creation of large malicious shortcut files disguised as legitimate documents. These .lnk files download JPEG images from cloud storage services, which appear to contain valid image headers but actually conceal encrypted malware code. The malware is revealed through multiple XOR decryption operations. Security researchers have identified the steganographic payload at offset 0x4201 within the images. The malware generates temporary files in the %LOCALAPPDATA% directory and executes through rundll32.exe, complicating detection. APT37 also uses fileless attack strategies, injecting shellcode into legitimate Windows processes and exploiting cloud services for command and control operations. Recent attacks have targeted South Korean organizations using social engineering tactics. Traditional antivirus solutions are inadequate against these techniques, prompting experts to recommend Endpoint Detection and Response (EDR) systems for real-time monitoring of anomalous activities.

Tech Optimizer

May 2, 2025

The Pillars of AI-Driven Security

The cybersecurity landscape has shifted from traditional methods like firewalls and antivirus software to more sophisticated, AI-driven strategies. The 2024 Verizon Data Breach Investigations Report identifies ransomware as a leading attack type, with a median time to compromise now measured in hours. The attack surface is expanding due to remote work, cloud adoption, and IoT devices, while traditional security measures struggle to keep up. AI enhances security across three domains: prevention, detection, and response. 1. Prevention: AI distinguishes between legitimate and suspicious activities, improving predictive accuracy and enabling proactive defenses against attacks. AI models can identify zero-day malware and fileless attacks by focusing on behavior. 2. Detection: AI-powered tools like SIEM systems analyze vast amounts of data to identify risks and suspicious patterns in near real-time, reducing false positives and highlighting low-and-slow attacks and insider threats. 3. Response: AI automates rapid containment and remediation actions, allowing human analysts to focus on more complex tasks. Generative AI can assist in drafting incident reports and suggesting remediation measures. AI-driven security offers scale and efficiency, reducing breach costs significantly for organizations that utilize it. AI models adapt to evolving threats, and AI tools help bridge the cybersecurity skills gap. However, challenges include potential biases in AI models, the need for talent and change management, and privacy concerns. Organizations are encouraged to adopt AI-driven security as a core component of their digital defense strategy to improve risk posture and threat response.

Tech Optimizer

March 3, 2025

Hackers Using PowerShell and Microsoft Legitimate Apps to Deploy Malware

Cybersecurity experts are reporting an increase in fileless attacks, where cybercriminals use PowerShell and legitimate Microsoft applications to deploy malware with minimal traces. These attacks have existed for over twenty years and are effective at evading traditional antivirus solutions. Attackers exploit PowerShell to download and execute malicious payloads directly in memory, complicating detection. They also utilize LOLBAS techniques, manipulating legitimate applications like BITS to execute malware. Memory injection techniques, such as Process Hollowing, allow attackers to disguise malware as legitimate processes. To combat these threats, cybersecurity professionals recommend deploying Endpoint Detection and Response solutions, enhancing memory analysis, enabling comprehensive PowerShell logging, and implementing PowerShell Constrained Language Mode. Organizations should also monitor Active Directory and conduct regular vulnerability assessments. Traditional file-based security measures are inadequate against these evolving threats, necessitating a shift to behavior-based detection and robust monitoring.