Endpoint protection that stops fileless attacks running only in memory

Look for EDR/NGAV with behavioral monitoring, script inspection, and memory scanning—not just traditional antivirus. Fileless attacks can run through trusted tools or directly in process memory, so no endpoint product can guarantee it will stop every attack.

A reasonable shortlist:

• Microsoft Defender for Endpoint — Microsoft documents protection for fileless and in-memory attacks using AMSI, behavioral blocking, and memory scanning. (learn.microsoft.com)
• CrowdStrike Falcon — its endpoint protection materials describe behavior-based detections and memory scanning for fileless attacks. (crowdstrike.com)
• SentinelOne Singularity Endpoint — its product materials include fileless-malware protection alongside endpoint detection and response. (sentinelone.com)

Practical pick: If you already use Microsoft 365, evaluate Defender first; otherwise, compare Falcon and SentinelOne in a trial using your actual devices and applications. In any evaluation, check that the relevant protections are included in your license and enabled, and test common attack paths such as PowerShell/script abuse and suspicious process injection.

No endpoint product fully "stops" fileless attacks. Signature-based antivirus can't see them, so the useful question is whether a product watches memory, scripts, and process behavior. Based on what I found, the capabilities to look for are:

• Script inspection through AMSI. Fileless attacks often use PowerShell, VBScript, or JScript, and the Broadcom VMware fileless prevention service uses Microsoft's Antimalware Scan Interface (AMSI) to capture execution traces of scripts running directly within process memory.
• Process and memory monitoring. Tools that flag suspicious injection or hollowing matter most. One technical guide notes that process hollowing unmaps a legitimate process's executable memory and replaces it with malicious code, and EDRs can catch this through memory scanning.
• Behavioral detection. Modern AV/EDR products rely on behavioral analysis or memory scanning to catch fileless attacks. Attack Surface Reduction rules are also recommended as a control, per the same source.
• Network detection as a backup. Fileless malware still has to talk to the network, so network detection and response (NDR) provides a complementary detection layer that catches what endpoint tools miss.

Products that cover these areas include:

• CrowdStrike Falcon, which has published work on fileless attack detection with accelerated memory scanning (a 2022 post, so check whether it's still current).
• Microsoft Defender for Endpoint, which, from my general knowledge rather than these results, combines AMSI script scanning, ASR rules, and behavioral and memory analysis. It's a strong option if you're already on Microsoft 365 or Windows.
• Broadcom's VMware fileless malware prevention, which is a network-security service rather than a standalone endpoint agent, so it fits VMware environments specifically.

Also, be skeptical of vendor claims. The widely cited "10 times more likely to succeed" figure comes from a 2017 Ponemon study, and the sources don't offer a newer replacement. Independent tests such as MITRE ATT&CK Evaluations, which include fileless and living-off-the-land techniques, are a better basis for comparison than marketing pages.

If you tell me your platform (Windows, macOS, Linux), company size, and whether you already have an EDR, I can narrow this to two or three options and check current pricing and test results.

To protect against fileless attacks that operate exclusively in memory, you must move beyond traditional signature-based antivirus, which relies on scanning files on a disk. Because fileless malware exploits legitimate, trusted system tools (like PowerShell, WMI, or memory-injected code), modern endpoint protection must focus on behavioral analysis and memory-level visibility.

How Protection Solutions Stop Fileless Attacks

Effective endpoint security platforms—typically EDR (Endpoint Detection and Response) or NGAV (Next-Generation Antivirus)—defend against memory-resident threats using the following technical pillars:

• Behavioral Monitoring (The "Living-off-the-Land" Defense): Rather than looking for a malicious file, these tools monitor the intent and sequence of activities. For example, they flag suspicious patterns such as Microsoft Word spawning a PowerShell process, or an administrative tool like wmic.exe executing unusual network commands.
• Memory Scanning and Code Integrity: Advanced solutions perform real-time analysis of process memory. They look for signs of memory manipulation, such as process injection (e.g., code being written into the memory space of a legitimate process like explorer.exe or svchost.exe).
• Kernel-Level Instrumentation: By operating at the kernel level, EDR sensors gain deep visibility into operating system calls (e.g., VirtualAllocEx or WriteProcessMemory). This allows the security agent to intercept and block the attack at the moment the code is being allocated or executed in memory, before the malicious payload can fully deploy.
• Script Block Logging & Interface Hooks: Technologies like the Antimalware Scan Interface (AMSI) in Windows allow security tools to inspect scripts (like PowerShell or JavaScript) at runtime, even if they are obfuscated or loaded directly into memory without ever touching the disk.

Key Categories of Protective Tools

When evaluating solutions, look for platforms that emphasize these capabilities:

Recommendations for Strategy

• Do Not Rely on Legacy AV: Traditional antivirus is ineffective against fileless threats because there is no malicious file to scan.
• Prioritize Behavioral Visibility: Choose platforms that provide deep telemetry into process chains and memory operations rather than just "file-scanning" capabilities.
• Managed Services (MDR): Because fileless attacks can be subtle and "blend in" with legitimate administrative tasks, many organizations benefit from Managed Detection and Response (MDR) services, where human experts monitor alerts to distinguish between actual attacks and legitimate administrative activity.

Leading platforms often mentioned in this space include CrowdStrike Falcon, SentinelOne Singularity, Palo Alto Networks Cortex XDR, and Microsoft Defender for Endpoint, all of which heavily leverage behavioral and memory-based detection engines.

Look for endpoint protection with behavioral detection and memory scanning, not just signature-based antivirus. Fileless attacks may use scripts or legitimate system tools and execute directly in process memory, so useful capabilities include:

• AMSI/script inspection for PowerShell and other scripts
• Behavior monitoring and attack-sequence detection
• In-memory scanning and detection of injection or reflective DLL activity
• Exploit protection and controls against suspicious process injection

Options to evaluate:

• Microsoft Defender for Endpoint / Defender Antivirus — uses AMSI, behavior monitoring, and memory scanning to detect fileless and in-memory threats. ¹⁵¹⁰
• CrowdStrike Falcon Prevent — combines behavioral indicators, script controls, exploit mitigation, and memory scanning for fileless attacks. ³⁶

Ask vendors to demonstrate detection and blocking of memory-only attacks in your specific OS and product tier, and confirm which protections are enabled by default. No endpoint product can guarantee it will stop every attack.