Virus Profile: W97M/Cobra.a1

Threat Search
Virus Profile information details
Risk Assessment: Home Low | Corporate Low
Date Discovered: 7/20/2002
Date Added: 11/21/2002
Origin: Unknown
Length: N/A
Type: Trojan
Subtype: Macro
DAT Required: 4220
Removal Instructions


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.

Indication of Infection

Deleted files.

Methods of Infection

Opening an infected document will execute the trojan.


W97M.DelAll.Trojan (NAV)

Virus Characteristics

This threat is detected as W97M/Cobra.a1. This small trojan contains one module - ComCity. On creating a new file, if the date is greater than the 11th day of October, November or December it will delete c:*.*.

Use current engine and DAT files for detection and removal.

It is very common for macro viruses to disable options within Office applications for example in Word, the macro protection warning commonly is disabled. After cleaning macro viruses, ensure that your previously set options are again enabled.

AVERT Recommended Updates:

* Office 2000 updates

* Malformed Word Document Could Enable Macro to Run Automatically (Information/Patch)


PC Infected? Get Expert Help

Virus Removal Service

Connect to one of our Security Experts by phone. Have your PC fixed remotely - while you watch!