Allaple Polymorphic Worm Technical Intelligence Dossier

Executive Summary & Threat Architecture

Allaple (also cataloged in threat research as Rahack, Net-Worm.Win32.Allaple, and W32/Allaple) is an infamous, self-propagating polymorphic computer worm first detected in 2006. Engineered to autonomously spread across internal networks and the public internet, Allaple weaponized a critical stack-based buffer overflow in the Windows Server Service (srvsvc.dll) canonicalize routine (CVE-2006-3439 / MS06-040). Operating over SMB TCP ports 139 and 445, Allaple generated massive sweeps of random IP addresses, blasting malicious NetprPathCanonicalize RPC requests that forced target machines to execute injected shellcode without any authentication or user interaction. Allaple is renowned for its advanced polymorphic XOR decryptor engine: upon infecting an executable file or spawning a new network propagation thread, the worm rewrote its entire decryption routine using randomly generated mathematical operations, registers, and junk instructions (NOPs, increment, decrement), fundamentally defeating signature-based antivirus detection at the time. Beyond autonomous propagation, Allaple executed local file infection across all fixed and removable storage drives, modifying PE executables (.exe and .scr) by appending its polymorphic shellcode to file headers. The worm generated such staggering volumes of outbound network scanning packets and ICMP echo requests that it routinely caused catastrophic denial-of-service conditions, collapsing corporate switches, saturating ISP uplinks, and knocking enterprise networks offline.

Observed Threat Aliases: Rahack, Net-Worm.Win32.Allaple, W32/Allaple, Worm.Allaple, Win32.Allaple.A

Ancestry & Lineage Tracking

Derived From / Upstream Ancestry: Proprietary origin

Documented Downstream Variants: allaple_a, allaple_b, rahack

Weaponized Vulnerabilities & Exploitation Topology

Documented common vulnerabilities and exposures (CVEs) weaponized by Allaple Polymorphic Worm operators for initial execution, sandbox evasion, or SYSTEM-level kernel privilege escalation:

→ Explore all 77 exploited vulnerabilities on the SystemHelpDesk CVE Threat Matrix Hub.

MITRE ATT&CK® Tactical Tradecraft

Tactics, techniques, and procedures (TTPs) systematically mapped across real-world intrusion kill-chains:

→ Inspect the complete 226-technique matrix on the MITRE ATT&CK Defense Hub.

Indicators of Compromise (IOCs) & Forensic Artifacts

Curated indicators for retrospective threat hunting across SIEM and EDR platforms:

Initial Delivery Vectors

• Autonomous network worm propagation exploiting NetAPI buffer overflow CVE-2006-3439 over SMB TCP port 445
• File infection of PE executables (.exe, .scr) on local and removable USB storage devices

Host Persistence & Execution Hooks

• Registry Run key under HKLM\Software\Microsoft\Windows\CurrentVersion\Run pointing to dropped copy in %SYSTEM32%
• Infection of existing legitimate system binaries to ensure execution upon user program launch

Reference File Hashes (SHA-256)

• 3e62f02cb8594d6e902b115ee877990155b46e38a202722b51ee2bc3a4ea8474
• 88a107ef4ef3b34208a0df70216b3f7f8d689626bc6594c9f187a27eb2a29c15