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RemoteConnection

Disable Echo Command! in MS_DOS

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well , we can disable echo command for security ... let's go on:

 

WARNING: make a backup copy of cmd.exe first!!

open cmd.exe ( if you don't know where is it, use windows search) with a hex editor, and then search for echo ... you should get this results :

0002F8D0 | 5000 4400 0000 0000 4100 5300 5300 4F00 | P.D.....A.S.S.O.

0002F8E0 | 4300 0000 4600 5400 5900 5000 4500 0000 | C...F.T.Y.P.E...

0002F8F0 | 4400 4500 4C00 0000 4500 4300 4800 4F00 | D.E.L...E.C.H.O.

0002F900 | 0000 0000 4500 4E00 4400 4C00 4F00 4300 | ....E.N.D.L.O.C.

0002F910 | 4100 4C00 0000 0000 4500 5200 4100 5300 | A.L.....E.R.A.S.

 

Now just change just change "4500 4300 4800 4F00" to "0000 0000

save and exit from editor ... now run cmd.exe :D

* edit to fix typo in Topic Title and add Topic Description *

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Would any one like to tell me what is " Echo Command " and for which purpose it is to be disabled...

Echo is basically a command to send back the output to you on your screen. For example, in command prompt, you can type "echo abc"., it simply writes "abc" on the next line. It's nothing but just for debugging or notification purposes. It does not execute any functions or make security changes.

As for RemoteConnection's post, I don't understand your point. At most I think the command prompt hangs and gives a blue screen of death or somewhat similar. Otherwise, the command prompt will not be executable as the hex codes have been changed. Even if it is still executable and nothing weird seem to happen, I don't think the effect will be as a security exploit. Hence, what is the effect of doing so? You should have stated its effects.
Edited by Inspiron (see edit history)

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Another thing is that how does the system recognize 16 Hex characters being replaced with only 8 Hex characters? and is this really a Security Issue? As noted above, all the MS-DOS echo command does is define the Std-output back to the display terminal.

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