need info re: possible trojan

  • Thread starter Thread starter johnyboy
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johnyboy

Windows on my system is set to show ALL files & folders.
However, scandisk shows 41,824,256 bytes in 190 hidden files.
I need some way to identify what kind of files these are & get
rid of them, (without having to go thru the hassle of reformatting my HD).
Is somebody hiding illicit files on my hard disk?
Are these files created by some sort of "remote administrative trojan?
 
johnyboy said:
Windows on my system is set to show ALL files & folders.
However, scandisk shows 41,824,256 bytes in 190 hidden files.
I need some way to identify what kind of files these are & get
rid of them, (without having to go thru the hassle of reformatting my HD).
Is somebody hiding illicit files on my hard disk?
Are these files created by some sort of "remote administrative trojan?

Showing all files and folders is not the same as changing the hidden
attribute of a file or folder. Making a file not hidden is accomplished
by entering the following.

attrib -h filename

Windows makes use of the hidden, system and read-only attributes to
prevent you from possibly deleting a file or directory that is necessary
for its operation, e.g. IO.SYS. Use a virus and/or adware scanner to
check for any other possibilites.

Danzer
 
(e-mail address removed) (johnyboy) wrote in
Windows on my system is set to show ALL files & folders.
However, scandisk shows 41,824,256 bytes in 190 hidden files.
I need some way to identify what kind of files these are & get
rid of them, (without having to go thru the hassle of reformatting my
HD). Is somebody hiding illicit files on my hard disk?
Are these files created by some sort of "remote administrative trojan?

If you want a text files showing what they all are and what folders
they're in, from a command prompt try:


cd \
C:\> dir */a:h/s > hidden.txt


As mentioned, hidden files are not bad boys by default.
 
johnyboy said:
Windows on my system is set to show ALL files & folders.
However, scandisk shows 41,824,256 bytes in 190 hidden files.
I need some way to identify what kind of files these are & get
rid of them, (without having to go thru the hassle of reformatting my HD).
Is somebody hiding illicit files on my hard disk?
Are these files created by some sort of "remote administrative trojan?

I did Al Bundy's command-line procedure on my machine and came up with 52.5
megs of hidden files--far more than I would have expected. At a quick run
through, there's nothing strange about them--chief larger offenders are
music and digital rights management (DRM) stuff and fonts. Besides these
there are profiles and bits of the OS that are important, as well as many
many little zero bit critters used for various purposes.
 
This procedure can be useful, on a system known to have been compromised: I
did the same search, using Al Bundy's command-line, on a machine which had a
number of virus/trojan infections, via IM or Kazaa channels. These
infections had been effectively negated via manual procedures, antivirus,
ad-aware, and Spybot Search & Destroy. However, a search today for hidden
files, turned up a cluster of such files, both apparent data files, and a
variety of randomly named executables, all with the same date, which I've
removed. These weren't active, but the data files probably contained
keystroke recording data which is better deleted, and I'd just as soon not
have the executables lying around, even though they weren't in use, or in
danger of being executed.

These weren't flagged by the antivirus--I may do some more work to see
why--i.e. submit them and see what they say.
 
However, a search today for hidden
files, turned up a cluster of such files, both apparent data files,

how did you tell & how did you know these were from a malicious source?
and a
variety of randomly named executables, all with the same date

what is the definition of a 'randomly named executables' - how did you know
they were random & malicious?
which I've removed

on a pc with so many infections & trojans, I would suggest baking up your
data & formatting the disk & reinstalling the o/s (then installing personal
firewall, applying all o/s patches, installing latest anti-virus & spybot
with immunsise on) before connecting to the internet
These weren't active, but the data files probably contained
keystroke recording data

how did you tell?
which is better deleted,

unless you have removed genuine o/s or app files...
and I'd just as soon not
have the executables lying around, even though they weren't in use, or in
danger of being executed.

how did you know they were not valid app or o/s files?
These weren't flagged by the antivirus--I may do some more work to see
why--i.e. submit them and see what they say.

may be a bit too late to submit them since you have already deleted them
 
erewhon said:
how did you tell & how did you know these were from a malicious source?
Can't tell for certain--but how many hidden executables with names
consisting of random strings of upper and lower case letters do you see on
an XP installation in \windows\system32?
what is the definition of a 'randomly named executables' - how did you know
they were random & malicious?

Named by apparently random strings of upper and lower case letters. Rather
different than most executables, and marked hidden. Did I say they were
malicious? I'm making an educated guess--from significant experience thank
you--based on the date/time stamps on the files and the hidden nature and
naming structure. I moved the executables to a separate directory, rather
than deleting them (that's what I meant by "removed.")
on a pc with so many infections & trojans, I would suggest baking up your
data & formatting the disk & reinstalling the o/s (then installing personal
firewall, applying all o/s patches, installing latest anti-virus & spybot
with immunsise on) before connecting to the internet

Good advice, but not necessary in this particular case, I think. There's no
further evidence of infection since the machine was cleaned some weeks ago.
how did you tell?

Couldn't tell--data not easily readable--I confess to guessing on this
point.
unless you have removed genuine o/s or app files...

Nope--I know how to determine if a file is part of Windows, and, as I said,
I moved them, rather than deleting them.

This is a fair caveat for the average person, but I'm very confident of my
ability to distinguish between legit parts of Windows and anything else.
Application files are a different kettle of fish--app vendors may do
anything. However, in my experience they don't throw hidden files with
unrelated and random naming structures into windows\system32.
how did you know they were not valid app or o/s files?

See above, and note that I covered by moving, rather than deleting.
may be a bit too late to submit them since you have already deleted them

See above.
 
Actually, although I'm quite clear that I know what I am doing and that what
I "quarantined" by moving it to a separate folder was, in fact, not useful
application software, I have to agree with "erewhon" that such action is not
something I would suggest to the average computer user--i.e. it's bad advice
to give others without regard to their level of experience.
 
erewhon said:
how did you tell & how did you know these were from a malicious source?


what is the definition of a 'randomly named executables' - how did you know
they were random & malicious?


on a pc with so many infections & trojans, I would suggest baking up your
data & formatting the disk & reinstalling the o/s (then installing personal
firewall, applying all o/s patches, installing latest anti-virus & spybot
with immunsise on) before connecting to the internet

As you probably know, some viruses can stay in the Master Boot Record of
your HD. The MBR is out of all your HD partitions, so if you're planning to
format your HD in order to get rid of viruses, don't forget to remplace your
MBR by a new one (clean). You can easily do this by launching this command
from a clean boot disk: "fdisk /mbr". After that, you can safely format your
HD.
how did you tell?


unless you have removed genuine o/s or app files...


how did you know they were not valid app or o/s files?


may be a bit too late to submit them since you have already deleted them

Best regards,
Mhyst
 
Mhyst said:
As you probably know, some viruses can stay in the Master Boot Record of
your HD. The MBR is out of all your HD partitions, so if you're planning to
format your HD in order to get rid of viruses, don't forget to remplace your
MBR by a new one (clean). You can easily do this by launching this command
from a clean boot disk: "fdisk /mbr". After that, you can safely format your
HD.

Make sure you are using the correct MBR for the system you
are trying to rebuild. Sometimes 'fdisk /mbr' can hose it up good.
 
FromTheRafters said:
Make sure you are using the correct MBR for the system you
are trying to rebuild. Sometimes 'fdisk /mbr' can hose it up good.

Good advice. As per the "make sure" -- be sure you make sure. Boot from
a trsuted boot disk and make sure you disable write. (the plastic
thingee is in see through state!)
 
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