The software maker's success stems partly from its ability to tightly tie applications to each other and to its flagship Windows operating system. Word and Excel, for example, use not only common scripting languages but also common components that make them easier to use and customize. But as Microsoft has increased the ties between applications and the operating system, particularly bundling Outlook with Office and hooking it to Internet Explorer, the company has created new security vulnerabilities, analysts say. One problem is Outlook's extensive dependence on Visual Basic and the ways hackers can exploit it. Another is the ease with which scripts can manipulate Outlook's address book and also affect the operating system regardless of other security measures, such as password protection.
Viruses are a long-standing problem.
In the past, system administrators contended with small windows of time during which infected files could get into their networks ahead of antivirus updates and be distributed by a few people, either inside or outside the organization. Here is your address book, so send out the virus to everybody there at the speed of your CPU instead of relying on the person dumb enough to send infected email. In the case of the Love bug, it isn't even a bug. It's just insecurely designed. Analysts say these recent outbreaks are similar to the Morris worm that a dozen years ago crippled Unix systems and brought down the young Internet.