Downloader-AUL.dr

This page shows details and results of our analysis on the malware Downloader-AUL.dr

Download Current DAT: 6616

Threat Detail

Malware Type: Trojan

Malware Sub-type: Dropper

Discovery Date: 2006-03-03

Next Steps:

Overview
Characteristics
Symptoms
Method of Infection
Removal

Overview

This is a trojan detection. Unlike viruses, trojans do not self-replicate. They are spread manually, often under the premise that they are beneficial or wanted. The most common installation methods involve system or security exploitation, and unsuspecting users manually executing unknown programs. Distribution channels include email, malicious or hacked web pages, Internet Relay Chat (IRC), peer-to-peer networks, etc.

Minimum DAT

4710 (2006-03-03)

Updated DAT

4710 (2006-03-03)

Minimum Engine

5.1.00

File Length

N/A

Description Added

2006-03-03

Description Modified

2006-03-23

Malware Proliferation

Characteristics

Downloader-AUL.dr detection is for a file that serves as a dropper component for other downloader trojans. Downloaders are designed to pull files from a remote website and execute the files that have been downloaded.

Upon execution, it drops following files:

explorer.exe (61,990 bytes) (Detected as Downloader-AUL)
svchost.exe (58,696 bytes) (Detected as PWS-Lineage)
explored.exe (20,007 bytes)
exploreo.exe (36,393 bytes)
PDLL.dll (105,984 bytes) (Detected as PWS-Lineage.dll)
ranx.dll (122,880 bytes) (Detected as BackDoor-CTV)
systemld.dll (24,064 bytes) (Detected as Downloader-AUL)
systemlo.dll (53,760 bytes) (Detected as PWS-Lineage.dll)
systemlr.dll (24,064 bytes) (Detected as Downloader-AUL)
wlmxa.exe (58,696 bytes) (Detected as PWS-Lineage)
wlmxb.exe (36,393 bytes) (Detected as PWS-Lineage.dr)
wlmxc.exe (27,083 bytes) (Detected as PWS-Lineage)

Following registry entries are added to run the trojans on system startup:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
"explored.exe"= ?%PROGRAMFILES%\explored.exe?
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
"exploreo.exe"= ?%SYSTEM%\exploreo.exe?
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
"explorer.exe"= ?%PROGRAMFILES%\explorer.exe?

Symptoms

Presence of files and registries listed above.

Method of Infection

N/A. Downloaders are not viruses, and as such do not themselves contain any method to replicate. However they may themselves be downloaded by other viruses and/or Trojans to be installed on the user's system.

Many of these additionally are mass spammed by the author to entice people into double-clicking on them.

Alternatively they may be installed by visiting a malicious web page (either by clicking on a link, or by the website hosting a scripted exploit which installs the Downloader onto the user's system with no user interaction.

Removal

A combination of the latest DATs and the Engine will be able to detect and remove this threat. AVERT recommends users not to trust seemingly familiar or safe file icons, particularly when received via P2P clients, IRC, email or other media where users can share files.