Quote

If you're going to test all passwords that contain uppercase letters, lowercase letters, numbers, and a few symbols, then that's 4,398,046,511,104 different passwords for a length of 7 characters

Quote

I know that the text is in English and I know that the password used to generate the key stream ,  is an English word with maximum 7 letters and minimum 3 letters

it is a lowercase word . How I know it because I read in the mind of the challenger . 

Quote

The problem here is that you have two variables to find out. There are three parts of the equation, input, password and output; two of which you don't know. You have only the output and you are trying to determine the password, but in order to determine the password you also need to know the input.

I know the input . The input is the ciphertext which is an RC4 cipher .

var input = "This is the input message";
var output = "LgYkO2JSfWoA394oOvXrwO4mtuDkusLCzg==";

we do not know the output . Because the output is the plaintext . So is not correcter to put the variable output as undefined like this :

var output = " ";

var t = toLowerCase(test);
if(t.indexOf(' the ') != -1 || t.indexOf(' and ') != -1 || t.indexOf(' is ') != -1){
   alert(test);
}

this is very brilliant

I

Quote

f you are changing specific parts of the registry, then back up those parts before you change them.  If you need to revert, instead of reverting the entire registry just do the parts you need to change back.  When you edit the registry you edit specific portions of it, it's not like you're changing the entire thing.  If you decide that you want to change the registry in order to run an executable, then just back up the keys and values that you're changing.

yes of course , only some keys should be changed and not the entire registry . However is not backing up one key then trying to restore it  dangerous as well ?

Quote

Experience tells me that If i'm thinking about restoring the registry, I'm probably going to get unexpected consequences.  So, I'll probably just reinstall the system and get a good night's sleep.

What if you want to change things in the registry many time in a different time ? you cannot reinstall your complete system every time . It makes no sense . So I do not think it is a good solution .

Quote

As usual, I have no idea what the context of your question is or what you've been researching or why

I , indirectly, answered this question in another topic . I said that I never got the opportunity to learn computer science at university or at the hands of any computer expert for reasons I cannot mention here in this forum . Therefore what I am searching for , through my questions ,  is LEARNING and PROGRESSING . The only method to achieve this is to ask and ask and ask and ask and ask and ask . Reading tutorials , books and articles  will provide me with information but will never make me progress . What makes me progress and become the best is asking . My questions seem weird , strange , stupid call them whatever you want but I do not see them like that . I do not even believe that there is a stupid question . It is all in the eyes of the beholder . It is like ugly and beautiful . It is all subjective . It is thanks to the questions that I asked in this forum , that you see as nonsense ,  that I learned and progressed . If I compare myself now with the time in which I first registered in this forum . You will bet I am far far better .  I read things I cannot understand and to which I find either NO answer in the internet or a stupid answer of an amateur who knows nothing or a very complicated answer of an expert . So , I ask in the forum . This forum is , honestly , the best ever . Now about the context of my question . I thought you know it . However if you do not know I will tell you : I have an EXE file . when I try to run it , it says windows could not find the exe file make sure you typed the name correctly and try again . I read in some articles , some of them I mentioned the link here in this forum , that by changing something in the registry , I can avoid the above error . So as changing things in registry is dangerous and backup of registry is bad idea , I wanted to know  a better and secure  method to backup the registry without jeopardizing my system. This is the context of the above question . Unfortunately , the second half answer of the guy  :

Quote

 Those could simply be replaced later to fully replace the state of the registry.

is from my  point of view vague so I asked for a technical explanation  .

Quote

(hint: it's you),

yes of course , you are right it is me : I am a newbie , inexperienced , unskillful . This is why I am here . You as an expert . You see my requests and questions  from the top of the mountain differently than me from the bottom of the mountain .

hello , what do you mean by

Quote

I would opt for a fresh install. 

?

I know that the text is in English and I know that the password used to generate the key stream ,  is an English word with maximum 7 letters and minimum 3 letters and of course I know the ciphertext . Based on all these information , brute forcing will not take a long time ,  it  will be the  efficient  and right method . the password lists , used in brute forcing  are of course in English ,  and  not a problem to get as I can find many lists using google . My only problem is that I cannot write the program that can do the brute force . I will , if I ever know how to write it , write it in javascript as it is the only language I know LITTLE about (better than nothing) . I have , absolutely , no idea about C++ , PHP or JAVA . Therefore I will write it in JAVASCRIPT .

the algorithm can be like this I guess :

1) I need a program that decrypt . So I need to know how decryption is done

2) the program should be linked with the password list files . So it will take or accept , for example ,  60 MB passwords

3) the program should know the right output that is the plaintext . How I do not know ? I mean how can  the bruteforcer determine that it has the plaintext ?

Quote

You need to have some idea what was encrypted -- and an appropriate test that will detect that output.

What do you mean by " appropriate test " ?

In this website , it is mentioned that registry backup is a bad idea :

https://superuser.com/questions/608066/is-it-possible-to-import-a-windows-registry-file-without-destroying-a-system

OK   could you please show me , step by step ,   how to fulfill this project ? Tell me please what to do step by step and from the beginning until the end

thanks

I do not understand what do you mean by :

Quote

It's the command to run when a file is opened.  In that case, it is saying the command is the actual filename, and to pass any other arguments after that. 

OK , lets suppose the password is a weak English word with 5 characters . So the password can be brute forced using a dictionary  attack . The problem is that I could not find a bruteforcer 

that could do the job for me and recover the password from the above script and as i am a newbie  , I cannot write my own . So what should I do ? could you please provide me with a good bruteforcer or if not possible help me write one or suggest another solution ?

Best regards

the file I am trying to run is the file with the text extension I sent to you . I changed its extension to .exe and I named it key then I run it as administrator but I got the above error .

Yes yes yes I did understand you very well but . It is only that I forget . Thank you for remembering me . I change the file to .exe and run it as administrator but to my surprise I got an error that says :

Windows cannot find key.exe make sure you typed the name correctly and try again . I did many researches , through googling the error , but none of the solutions I found in google helped me solve my problem . I am lost and really stuck and do not know how to solve my problem . Help

In the second link the following is mentioned :

Quote

 

HKEY_CLASSES_ROOT\exefile

7.With exefileselected, right-click (Default) and click Modify…

8.Change the Value data: to "%1" %*

9.Browse to and then click on the following registry key:

KEY_CLASSES_ROOT\exefile\shell\open

10.With openselected, right-click (Default) and click Modify…

11.Change the Value data: to "%1" %*

 

why should a name of a command or a program , in the context menu , changed to "%1" %*  in order to avoid this error :

can’t open .exe files in Windows 7

?

I do not understand . I think you should take a look at the video , which is 2 minutes and 50 seconds , short , in order for you  to be able to answer my question .

In this website :

http://www.howtocreate.co.uk/emails/test_RC4B64_js.htm

When you clicked on the Download the script  , you get a script . I know exactly what the script does . The script decrypts and encrypts based on a password   . In the encryption process , the script asks for the password and the plaintext . From the password , a key stream will be created . Then , the created key stream will be  XORED  with the plaintext to give an RC4  cipher which , in return, is encoded to base 64 .  the decryption process is the reverse of the encryption process. Anyway . My question is the following : Based , only , on  these two information : 1) the ciphertext and  2)the script in the Download the script section is it possible to recover or hack or crack  the password if we do not know it or we forget it ?

In these two websites :

https://www.youtube.com/watch?v=Ux3iMvyS7to

https://social.technet.microsoft.com/Forums/en-US/db35e055-fb5a-43a0-b478-a238a69b438a/quot1quot-mean-virus?forum=w7itprogeneral

the following symbol  "%1" %*   is mentioned . What is it ? could you , please ,  explain to me what is it exactly ?

Best regards

Quote

If it's an executable, then you don't need a program to open it, you can just execute it

how ? you mean by double click on it ?

Quote

though, we've already had this discussion in another topic

Could you provide me with  the link of the other topic so that i can revise it again because I do not know where did we have the same discussion

Quote

You can't really tell just by looking at binary data

in the .text file , there no binary data but a garbage of Unicode characters

Quote

Well, the only information about the file that you have, other than the name, is the contents

I have a file with a text extension . When I opened it with a notepad , I noticed , apart from the plain text in it , thousands of  garbage characters . Let me apply what I learnt : the extension does not tell anyone anything . Therefore I need to look at the content . The content is a mixture of Unicode-like garbage characters , in its majority , and plain text , in its minority . I think , based on the content of that text file , it is an EXE  but i am not sure . I can be wrong . Could you please , look at the file content and tell me , suppose you have an approximate  idea ,  what is the right program , based on its content of course ,  to use to open it  ? because  I am sure it is NOT notepad . I attached the file with my post

.text

OK , if the file extension does not tell anyone anything and if it is up to the programmer to decide the name of the extension and how the file should be opened and so on ... how am I  supposed to know , faced with a file ,  what is the right program to use to open it !? I cannot meet the programmer who programmed it to ask him

So what should I do then ?

Quote

Remember that the part after the dot in a filename is just as meaningless as the part before it

1) with due all respect , Sir , I do not agree with you . The file extension is not meaningless because it tells with what program should the file be opened . If you have a jpg extension file , that is a photo ,  and try to open it with a Winrar program or any other program  instead of a photo viewer  ,  the photo will not be opened and an error will be triggered . The extension tells with what program should the file be opened . Moreover , if I change the extension of the photo from jpg to txt and open it with notepad will I be able to see a photo ? no , i will see garbage characters in the text file . So how can you tell me that the extension is meaningless ?

2) in this link : http://www.winimage.com/zLibDll/minizip.html

it is mentioned the following :

Quote

Now, with version 1.23 and 1.14 of zLib, the Minizip library is inlucded in the contrib/minizip directory

which is the case for me . So I have minizip library in the contrib/minizip directory and I read all the files there like configure , makefile , minizip64-info.txt ... but i do not know how to compile minizip as it is not mentioned how to compile it in the above files . and not in the whole zlib directories

You mean that my compilation succeeded and that the above files I got , after compilation , are the right files  ?? should not I get , for example , after compilation , a file with a DLL extension ? Are these above files what I am supposed to get after compilation of zlib source code ?

You are the best justsomeguy . The problem is solved and I do not see the error anymore . Here is the result :

$ make test
gcc -O3 -I. -c -o example.o test/example.c
gcc -O3  -c -o adler32.o adler32.c
gcc -O3  -c -o crc32.o crc32.c
gcc -O3  -c -o deflate.o deflate.c
gcc -O3  -c -o infback.o infback.c
gcc -O3  -c -o inffast.o inffast.c
gcc -O3  -c -o inflate.o inflate.c
gcc -O3  -c -o inftrees.o inftrees.c
gcc -O3  -c -o trees.o trees.c
gcc -O3  -c -o zutil.o zutil.c
gcc -O3  -c -o compress.o compress.c
gcc -O3  -c -o uncompr.o uncompr.c
gcc -O3  -c -o gzclose.o gzclose.c
gcc -O3  -c -o gzlib.o gzlib.c
gcc -O3  -c -o gzread.o gzread.c
gcc -O3  -c -o gzwrite.o gzwrite.c
ar rc libz.a adler32.o crc32.o deflate.o infback.o inffast.o inflate.o inftrees.o trees.o zutil.o compress.o uncompr.o gzclose.o gzlib.o gzread.o gzwrite.o
gcc -O3 -o example.exe example.o -L. libz.a
gcc -O3 -I. -c -o minigzip.o test/minigzip.c
gcc -O3 -o minigzip.exe minigzip.o -L. libz.a
hello world
zlib version 1.2.11 = 0x12b0, compile flags = 0xa9
uncompress(): hello, hello!
gzread(): hello, hello!
gzgets() after gzseek:  hello!
inflate(): hello, hello!
large_inflate(): OK
after inflateSync(): hello, hello!
inflate with dictionary: hello, hello!
                *** zlib test OK ***

but I am really still confused . After  building ,  I do not see any EXE  file . Instead , I got these files and folders :

folders : include , lib , share

files : zconfig.h , zlib.h , zlib.pc , libz.a , zlib.3

What I am missing?

OK , I read them as you told me . and in the README file it is mentioned how to compile it . Now , however , I have another problem which is more complicated than the first :

During the building process in cygwin , I got this error :

$ ./configure
Checking for gcc...
Checking for shared library support...
No shared library support.
Building static library libz.a version 1.2.11 with gcc.
Checking for size_t... Yes.
Checking for off64_t... No.
Checking for fseeko... Yes.
Checking for strerror... Yes.
Checking for unistd.h... Yes.
Checking for stdarg.h... Yes.
Checking whether to use vs[n]printf() or s[n]printf()... using vs[n]printf().
Checking for vsnprintf() in stdio.h... Yes.
Checking for return value of vsnprintf()... Yes.
Checking for attribute(visibility) support... No.

$ make test
gcc -O3 -I. -c -o example.o test/example.c
gcc -O3  -c -o adler32.o adler32.c
gcc -O3  -c -o crc32.o crc32.c
gcc -O3  -c -o deflate.o deflate.c
gcc -O3  -c -o infback.o infback.c
gcc -O3  -c -o inffast.o inffast.c
gcc -O3  -c -o inflate.o inflate.c
gcc -O3  -c -o inftrees.o inftrees.c
gcc -O3  -c -o trees.o trees.c
gcc -O3  -c -o zutil.o zutil.c
gcc -O3  -c -o compress.o compress.c
gcc -O3  -c -o uncompr.o uncompr.c
gcc -O3  -c -o gzclose.o gzclose.c
gcc -O3  -c -o gzlib.o gzlib.c
gzlib.c: In function ‘gz_open’:
gzlib.c:243:20: warning: implicit declaration of function ‘_wopen’; did you mean  ‘fwopen’? [-Wimplicit-function-declaration]
         fd == -2 ? _wopen(path, oflag, 0666) :
                    ^~~~~~
                    fwopen
gcc -O3  -c -o gzread.o gzread.c
gcc -O3  -c -o gzwrite.o gzwrite.c
ar rc libz.a adler32.o crc32.o deflate.o infback.o inffast.o inflate.o inftrees.     o trees.o zutil.o compress.o uncompr.o gzclose.o gzlib.o gzread.o gzwrite.o
gcc -O3 -o example.exe example.o -L. libz.a
libz.a(gzlib.o):gzlib.c:(.text+0xab2): undefined reference to `_wopen'
libz.a(gzlib.o):gzlib.c:(.text+0xab2): relocation truncated to fit: R_X86_64_PC3  2 against undefined symbol `_wopen'
libz.a(gzlib.o):gzlib.c:(.text+0xc50): undefined reference to `_wopen'
libz.a(gzlib.o):gzlib.c:(.text+0xc50): relocation truncated to fit: R_X86_64_PC3  2 against undefined symbol `_wopen'
collect2: error: ld returned 1 exit status
make: *** [Makefile:289: example.exe] Error 1

I checked this link for help :

https://stackoverflow.com/questions/42537454/compiling-gcc-7-20170212-on-windows-7-64-with-cygwin-wopen-error

There is it is mentioned :

Quote

That said, to build zlib on Cygwin the following patches are needed: https://github.com/Alexpux/MSYS2-packages/raw/master/zlib/1.2.11-cygwin-no-widechar.patch
https://github.com/Alexpux/MSYS2-packages/blob/master/zlib/1.2.7-zlib-symbols.patch

but it is not mentioned how these patches are done . I do not know how to do those patches . Or if there is another solution for how to solve the above error , I will be very thankful and glad to see it . 

Thank you for your reply justsomeguy . After reading your reply , which helped me , I , now ,  know how to compile a single C or C++ source code  using GCC and G++ in Cygwin windows . However , the ZLIB folder I installed from the https://zlib.net/  website  has many source code files with .C and .CPP extensions . In addition to that ,  it has many different other files with different extensions like  MSC ,  RAW , PAS , ADB , ADS

1) what I know is that the only files I should compile , using command lines with GCC and G++ compilers  in cygwin , are the ones with .C and .CPP  extensions (if I am wrong please correct me ) . There are , in the ZLIB folder , however , many files with .C and .CPP . should they ALL be compiled or SOME of them ? if they should all be compiled ,  should I compile them one by one  or all in the same time ? and  If I should compile them all in the same time , should I put them together in a one separated folder then compile them at once ?   because they are scattered  in different folders . Or It is enough to write there names all  in Cygwin in one command line and thus Cygwin compiler will compile them all in the same time ?

2) what are the roles of the other different extensions i mentioned above ? for example PAS extension is pascal . What has pascal to do with our zlib program written in C ? RAW extension is used by cameras what has this to do with zlib program for compression and decompression and the same for ADB and ADS which are database files ????

I have windows 7 64 bit and Cygwin installed on it . I have zlib open source version 1.2.11 from https://zlib.net/ . I would like to compile it using Cygwin but I have no idea how to do it from the beginning til the end and step by step . Although I googled in the internet about how to compile zlib in cygwin , not only I did not find many articles , but the few I found were of no help to me as they do not show how to do the work step by step and in a simple way . Moreover , I read the zlib manual but there is not mentioned how to compile zlib . So any help on how to compile zlib in cygwin will be really appreciated

thank you very much