Allaple

Overview

Worm:Win32/Allaple is a highly aggressive, polymorphic network worm notorious for rapidly propagating across Local Area Networks (LANs) and causing severe network congestion and Denial of Service (DoS).

What is Allaple?
For general users, an Allaple infection results in a severely sluggish computer and an unusable network connection. For incident responders, Allaple is a classic, catastrophic network threat. Unlike modern, stealthy malware, Allaple is incredibly noisy. Once it infects a host, it immediately begins violently scanning the local subnet and external IP ranges, attempting to exploit known vulnerabilities (such as older DCOM RPC or SMB exploits) to replicate itself onto as many machines as possible.

Infection Vectors & Threat Hunting
Allaple is a self-propagating worm. Once a single machine on a network is infected (often via a malicious email attachment or compromised USB drive), the worm takes over. It utilizes advanced polymorphism; every time it replicates, it changes its file size, code structure, and icon to evade static antivirus signatures. Threat hunters will instantly identify an Allaple outbreak by observing massive, sustained spikes in outbound TCP traffic on ports 135, 139, 445, and various random high ports. The infected host effectively acts as a localized DoS attack against the corporate firewall and switches.

Forensic Analysis & Impact
The impact of Allaple is network paralysis. EDR platforms frequently detect Allaple based on its aggressive network scanning and attempts to drop randomly named, polymorphic executables into the %SystemRoot% directory. Incident responders must utilize network segmentation immediately to quarantine the infected subnets, as the worm will spread faster than manual remediation can occur.

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to the MITRE ATT&CK framework:

Tactical Mitigations

Based on the techniques used by this family, consider the following defensive strategies:

• T1105: Implement network intrusion detection systems (NIDS) and host-based firewalls to block unauthorized inbound or outbound file transfers.

Generated Detections (Boilerplate)

These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.

YARA Rule

rule MALWARE_WIN_ALLAPLE {
    meta:
        description = "Detects Allaple (worm)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "allaple" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Allaple Activity
id: 6af5a0fd5806233e789dc73ffc166391
status: experimental
description: Detects generic indicators of the allaple malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*allaple*"
    condition: selection
level: medium

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Immediately physically disconnect the infected endpoint from the network switch; Allaple will paralyze the local subnet with scan traffic.
2. Deploy network segmentation and firewall rules to block lateral traffic on TCP ports 135, 139, and 445 to halt the worm's propagation.
3. Utilize a reputable, updated antivirus scanner to remove the polymorphic Allaple executables from the <code>%SystemRoot%</code> directory.
4. Ensure all machines on the network are fully patched against historical DCOM RPC and SMB vulnerabilities to prevent reinfection.

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not leave the machine connected to the network during triage; the sheer volume of outbound scanning will crash corporate routers.
2. Avoid relying solely on file hashes (MD5/SHA-256) to hunt for Allaple; its polymorphism ensures every dropped executable is unique.

References & External Analysis

• Search "allaple" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: worm)

Explore other malware families in the same category:

• Conficker
• Vobfus
• Beebone
• Chir
• Pykspa

Machine-readable

Get this profile as JSON: https://jordan123234-malware-families-explorer.static.hf.space/api/allaple.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.