诡异事件:神秘跨平台病毒badBIOS

2013-11-04 196857人围观 ,发现 47 个不明物体 资讯

badbios

三年前,安全顾问、Pwn2Own黑客挑战赛创始人Dragos Ruiu在实验室里注意到一件非同寻常的事情:

刚刚全新安装OS X的MacBook Air笔记本自动更新了BIOS固件,之后当他试图从CD ROM启动机器时遭到了拒绝,他还发现机器会不做任何提示删除数据和撤销配置更改。

随后几个月,事情越发离奇,仿佛是出自科幻惊悚片:一台运行Open BSD的计算机也开始不做任何提示删除数据和更改配置。

他的网络专门通过IPv6传输数据,即使关闭了IPv6协议也没用。最最难以置信的是,拔掉电源线和网线、移除Wi-Fi和蓝牙网卡的被感染机器也能传输网络数据。神秘的BIOS固件病毒badBIOS还能感染Windows和Linux。深入调查分析发现,只有在移除内部扬声器和麦克风之后,抓包工具才发现不再有数据包传输。Ruiu指出,这个恶意程序能利用扬声器和麦克风在计算机之间进行高频传输。badBIOS并不是利用扬声器麦克风传播病毒,而是通过麦克风在被感染机器之间进行通信,就像是彼此之间联网。

[via/Solidot]

这些评论亮了

  • test 回复
    太牛逼了吧
    )9( 亮了
  • aoebug (1级) 回复
    设备之间用麦克风和扬声器聊天....?
    )9( 亮了
  • anlfi (5级) 回复
    Sound Distance Frequency
    People often mistake the sample frequency for the audio frequency.
    Audio speakers can clearly reproduce frequencies between 20Hz-20kHz, the human hearing range, but not much more. Even if audible, these high frequencies are indiscernible beeps.
    To digitally describe a sound wave one must sample this wave with an AD convertor. Open the link to the image. http://en.wikipedia.org/wiki/File:Pcm.svg . This shows one fase of a sine wave (in red).
    An AD convertor takes snapshots (in gray) of the sounds amplitude at an interval. In the case of the image that is 32 times per fase/cycle (horizontal resolution). There is no mention of sound frequency in this image, so if the sound frequency in the image is 100 Hz, the sample frequency would be 3200 Hz. A higher frequency means a crisper sound.
    Had this sample rate been equal to the sound frequency, the ADC samples only every fase, wich means it measures the similar outbreaks every fase, wich creates a flatline, hence no sound. A sample rate of 44.1 kHz (CD quality) can playback a square wave at 22.05 kHz, not higher (Nyquist frequency) and nothing more then a square (see the grey blocks). The lower the audio frequency, the better the quality of characteristics. Or raise the sample frequency. For playback of audible sound 44.1 kHz suffices more then enough.
    When tuning down the sound (making baby cries sound like lion growls, or make mosquito like a B17) a much higher sample frequency is needed to clearly represent the edited sound. Hence the 96 kHz in studios.
    The same goes for the 16 vs 24 bit pcm sound misconception. This describes amplitude (vertical resolution in the image, wich is a mere 4 bit). Sixteen bit is enough, unless you are editing very soft sounds. Then you use 24 bit wich is 256 times more precise.
    Picking up audio to monitor certain activity is very well possible, but the frequencies at wich this happens are a limited.
    I thought I should clear this up.
    )8( 亮了
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