Invisible <voi### [at] devnull> wrote:
> - You *cannot* take CCTV footage, enlarge it 20x, "run an imagine 
> enhancement algorithm" and then read a car numberplate from 300 yards. 
> It doesn't work like that.

  Actually it's not *that* far-fetched. When one understands the basics of
image manipulation and computers, it's intuitive to think that image data
that's so noisy or blurry is so destroyed that no useful information can be
retrieved from it. However, in many cases the information isn't *completely*
destroyed and there are very clever heuristic algorithms to try to guess
what the information was. This is especially true if you have video footage
instead of one single still image (because the combined information of
video footate can amount to a significant amount of the original information;
noise averages out, and any kind of movement will give sub-pixel-sized pieces
of information which can be used for interpolation; even a very low-resolution
video can give surprising amounts of information when you take into account
movement).

> - IP addresses are generally *not* "registered" to individual human 
> beings in the same way that telephone numbers are. Generally they are 
> just registered to your ISP (for home customers) or your employer (if 
> you're doing this from your place of work).

  The ISP knows which one of their clients has which IP address at any
given moment, and they usually have in record the home address of their
clients. While the computer might not be at this home address, it's most
often so. Thus *in theory* it could be possible to locate any individual
by IP address (even if it's behind a NAT), assuming you also hack into the
ISP's client database to get the home address.

  (In many countries that would be illegal, though, at least without a
court order.)

> - If an attacker is "marking their signal by bouncing it off proxy 
> servers all over the world", the geographic locations of those servers 
> do not magically pop up on a world map when you try to "backtrace the 
> signal".

  Actually IP addresses can be mostly mapped on a world map. That's how
they track eg. internet traffic amounts per country. (This is especially true
if the proxy servers are owned by ISPs, as their locations are known, and
IP addresses can be attributed to ISPs because that's public information.)

  Of course *showing* such a map on the fly is just for the viewers.

> - There is no such thing as "a steganography detection algorithm". 
> That's kind of the entire *point* of steganography; you can't detect it.

  I wouldn't claim that without some actual references.

> - If you "upload the firmware" from a device onto your computer, it 
> *canoot* infect your computer with a virus that secretly steals your 
> data or modifies computer evidence. You see, a virus doesn't *do* 
> anything - anything at all - unless you actually *run* it. Any 
> half-competent computer forensics expert wouldn't make such a mistake. 

  So-called zero-day exploits can sometimes surprise even the best
experts (which is why they are extremely valuable in the cracker community),
and there have been cases where a buggy computer can be made to execute
code from the outside (or, at the very least, there have been cases that a
computer could be made to crash by just sending it certain IP packets).

> Also, something bothers me: I'm PRETTY SURE that if a suspect refuses to 
> give you a DNA sample, then you CANNOT simply offer them a drink, and 
> then lift their fingerprints and DNA from the glass afterwards. It 
> strikes me that there must be some kind of LAW against that kind of 
> thing. (Otherwise why would you even need consent in the first place?)

  The DNA obtained that way cannot be used as evidence, but it can rule
out or confirm a suspect, so that further investigation can be directed
better. But I don't know if even doing that is legal.

-- 
                                                          - Warp

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