WDEF B Virus

Alias:---
Strain:WDEF Virus Strain
detected when:March 1991
where:Hannover,Germany
Classification:File infector only Desktop file
Length:Resource fork extension: 1842 bytes

Preconditions

Operating System(s):MacOS proprietary
Version/Release:System 4.1 or greater , not 7.0
Computer model(s):Apple Macintosh: all models
Caroname:WDEF.B

Attributes

Easy identification:Additional WDEF 0 resource in Desktop file; Desktop shouldn't have one.

Type of Infection:

Only Desktop files

Infection Technique:Desktop File: WDEF 0 1842 Bytes.
Infection Trigger:Executing an infected Desktop file and a random algorithm produces the value 1 long and the availability of SysEnvirons-Trap; the random value is calculated using the RandomSeed system variable.
Storage Media affected:
Interrupts hooked:Only during infection: Write, AddResource, ChangedResouse, WriteResource, UpdateResFile
Stealth:
Tunneling/Selfprot:
Oligo/Polymorphism:
Encoding Method:
Damage:Permanent damage: --- Transient damage: Only when running under MultiFinder. Only first launched application: if the application has a menu that displays font-size-information using the system, available font sizes are no longer displayed outlined; all sizes are displayed in normal style. Switching between applications doesnot change the first application's behavior.
Damage Trigger:Running an infected Desktop file.
Particularities:No infection on systems without SysEnvirons. Virus beeps once if infected application is run.
Similarities:CDEF, WDEF A

Agents

Countermeasures:1.Use an anti-viral product (public domain or commercial) such Disinfectant, Interferon, Virus detective or VirusRx to scan for virus signature. 2.Use a protection INIT called Eradicat'Em that prevents WDEF infection (also prevents CDEF infection)
Standard means:

Acknowledgements

Location:Virus Test Center, University Hamburg, Germany
Classification by:Ronald Greinke
Documentation by:Ronald Greinke
Date:17-December-1991
Information Source:---

(c) 1996 Virus-Test-Center, University of Hamburg