programs or disks they infect. This is not an intentional act of the virus, but simply a result of the fact that many viruses contain extremely poor quality code An example, one of the most common past viruses, Stoned, is not intentionally harmful fortunately, the author did not anticipate the use of anything other than 360KB floppy disks The original virus tried to hide its own code in an area of 1. 2mb diskettes that resulted in corruption of the entire diskette( this bug was fixed in later versions of the virus) 参考译文 病毒的行为攻击阶段 许多病毒会做一些不太令人愉快的事情,比如删除文件或者改变磁盘上的随机数据,冒 充打字稿或者只是降低PC的速度:一些病毒做一些不太有害的事情,比如播放音乐或在屏 幕上显示一些信息或动画。如同感染阶段需要一些事件触发一样,攻击阶段也有它自己的触 发条件 这是否就意味着一个没有攻击阶段的病毒就是良性的呢?不。许多病毒其自身都有 bug,这些bug会产生一些未知的消极影响。此外,即使病毒设计完美,它仍会盗用系统资 病毒可以通过当它们拥有充足条件时才开始传播的方法来推迟暴露它们的存在。这意味 着攻击可能会被推迟到最初感染后的几天,几星期,几个月甚至几年才会发生 攻击阶段是可选择性的,许多病毒的攻击只是简单地进行复制并且没有触发因素。是否 这就可以说这些是“好”病毒呢?不!任何不经过你允许而在你磁盘上复制自己的东西都会 盗用内存和CPU资源 有些病毒只会“感染”而没有攻击阶段,但它们会破坏被它们感染的程序或磁盘,这反 而更有害。这并不是这些病毒想要做的事情,而是因为它们中含有很差的代码所带来的后果。 举一个例子,一个过去最普通的病毒— Stoned—一并没有明确的破坏性。但不幸的是,病 毒的编写者并没有预见到不同于360KB软盘的其他磁盘的使用。最初的病毒试图把它自身 隐藏在1.2MB的磁盘中从而导致整张磁盘变坏(在这个病毒后来的版本中,这个bug已经 修复)。 Text 4 Number of viruses In 1990, estimates ranged from 200 to 500; then in 1991 estimates ranged from 600 to 1, 000 different viruses. In late 1992, estimates were ranging from 1, 000 to 2, 300 viruses. In mid-1994, the numbers vary from 4, 500 to over 7, 500 viruses. In 199 the number climbed over 10,000 1998 saw 20,000 and 2000 topped 50,000 It's easy to say there are more now The confusion exists partly because it's difficult to agree on how to count viruses. New viruses frequently arise from someone taking an existing virus that does something like put a message out on your screen saying"Your PC is now stoned"and changing it to say something like Donald Duck is a liar!". Is this a new virus? Most experts say yes. But, this is a trivial change that can be done in less than two minutes resulting in yet another"new"virus Another problem comes from viruses that try to conceal themselves from scanners by mutating. In other words, every time the virus infects another file, it will try to use a different version of itself. These viruses are known as polymorphic viruses One example, the Whale(a huge clumsy 10,000 byte virus), creates 33 different versions of itself when it infects files. At least one person counts this as 33 different viruses on their list. Manyprograms or disks they infect. This is not an intentional act of the virus, but simply a result of the fact that many viruses contain extremely poor quality code. An example, one of the most common past viruses, Stoned, is not intentionally harmful. Unfortunately, the author did not anticipate the use of anything other than 360KB floppy disks. The original virus tried to hide its own code in an area of 1.2MB diskettes that resulted in corruption of the entire diskette (this bug was fixed in later versions of the virus). 参考译文 病毒的行为——攻击阶段 许多病毒会做一些不太令人愉快的事情，比如删除文件或者改变磁盘上的随机数据，冒 充打字稿或者只是降低 PC 的速度；一些病毒做一些不太有害的事情，比如播放音乐或在屏 幕上显示一些信息或动画。如同感染阶段需要一些事件触发一样，攻击阶段也有它自己的触 发条件。 这是否就意味着一个没有攻击阶段的病毒就是良性的呢？不。许多病毒其自身都有 bug，这些 bug 会产生一些未知的消极影响。此外，即使病毒设计完美，它仍会盗用系统资 源。 病毒可以通过当它们拥有充足条件时才开始传播的方法来推迟暴露它们的存在。这意味 着攻击可能会被推迟到最初感染后的几天，几星期，几个月甚至几年才会发生。 攻击阶段是可选择性的，许多病毒的攻击只是简单地进行复制并且没有触发因素。是否 这就可以说这些是“好”病毒呢？不！任何不经过你允许而在你磁盘上复制自己的东西都会 盗用内存和 CPU 资源。 有些病毒只会“感染”而没有攻击阶段，但它们会破坏被它们感染的程序或磁盘，这反 而更有害。这并不是这些病毒想要做的事情，而是因为它们中含有很差的代码所带来的后果。 举一个例子，一个过去最普通的病毒——Stoned——并没有明确的破坏性。但不幸的是，病 毒的编写者并没有预见到不同于 360KB 软盘的其他磁盘的使用。最初的病毒试图把它自身 隐藏在 1.2MB 的磁盘中从而导致整张磁盘变坏（在这个病毒后来的版本中，这个 bug 已经 修复）。 Text 4 Number of Viruses In 1990, estimates ranged from 200 to 500; then in 1991 estimates ranged from 600 to 1,000 different viruses. In late 1992, estimates were ranging from 1,000 to 2,300 viruses. In mid-1994, the numbers vary from 4,500 to over 7,500 viruses. In 1996 the number climbed over 10,000. 1998 saw 20,000 and 2000 topped 50,000. It's easy to say there are more now. The confusion exists partly because it's difficult to agree on how to count viruses. New viruses frequently arise from someone taking an existing virus that does something like put a message out on your screen saying "Your PC is now stoned" and changing it to say something like "Donald Duck is a liar!". Is this a new virus? Most experts say yes. But, this is a trivial change that can be done in less than two minutes resulting in yet another "new" virus. Another problem comes from viruses that try to conceal themselves from scanners by mutating. In other words, every time the virus infects another file, it will try to use a different version of itself. These viruses are known as polymorphic viruses. One example, the Whale (a huge clumsy 10,000 byte virus), creates 33 different versions of itself when it infects files. At least one person counts this as 33 different viruses on their list. Many