Jean5

Hi all

I'm looking forward to purchase ExeCryptor (www.strongbit.com) to protect my shareware. But before I'd like to know independent opinions/experience if any.

My question is: Anybody uses execryptor? Can you tell me smth about? Are there some problems? Is it cost-effective?

Thank you in advance for any reply

Jean

nnxion

Well, I have not tried it, but think about it logically. You would think that big companies would all use this if this were a magic product. But all of the software that those big companies make, is cracked.

Basic message: Anything that's runnable is crackable. It just might take them a bit longer to crack it with software like ExeCryptor.

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BillyColl

Yeah you're right everything is crackable.

As for "anything runnable is crackable" I can assume you mention usually protectors decrypt program code when it's running and then it can be analysed and cracked by an intrusion tool. But ExeCryptor never decrypts the code. It obfuscates it and the app runs in obscured state. That's why I find it a little stronger than other existing protectors

kruptof

That is a very bold statement dude...........................i believe most software can be carck but it is not very easy nor is it very quick..... i think software like TrueCrypt will never be easy to crack....or maybe they are uncrackable (just a thought)

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Ooble

Yet it can still be cracked.

If you do decide to purchase it, remember, your application will only be as strong as its weakest link. If you obscure the program code to the point that the greatest hacker in the world would take years to decrypt it, but store the number of days the program's been running as an unencrypted registry key, you'll still be buggered.

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msk420

Everything can be cracked no matter how much you encrypt it. Any program that has and encryption program running on it can still be cracked. All it might do is take the person who is cracking it more time. Trust me things that can be cracked will be cracked and everything can be cracked.

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Code Forums

BillyColl

It sounds like "Why to live? Anyway ** will die..."

Good protection will delay cracking. And in the case of EXECryptor as it is regularly updated when the current version will be bypassed there already will be new improved and updated one.

msk420

dude?

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Dameon

Security through obfuscation isn't security at all.

Every trial period, every CD requirement, every aspect of operation is entirely changeable. You can make it harder, but the end-user CPU and storage media are not under your control. Your executable can be changed, protections disabled, or what have you. It does matter how the software you intend to purchase goes about "securing" your insructions...the same instructions (or some equivalent) at one point or another get executed in the same effective order, no matter what order or form they are stored in. All the instructions are sitting in memory as they execute, wide open to whatever kernel-mode facilities want to look at it, and that's just a hard fact about the way computers work.

With that considered, perhaps you will realize that such software is a waste of money.

I especially love how they advertise it as "bulletproof" and "unbreakable." Golden.

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MD5(sig) = bcef75433db02e9ad9bf81d6f7c5c270

BillyColl

EXECryptor 2.x version from http://www.strongbit.com starting to use
Code morphing launched in July
2004 remains uncracked. Whatever anybody says in practice 2 years to be
unbroken I think it's very good for an app protector

To explain better what is EXECryptor and Code Morphing I cite beow the description and examlpe:

"EXECryptor is a software tool that provide developers with software protection from reverse engineering, analysis and modifications. Its main difference from other protection tools is its code transformation called "Code Morphing". This technology protects the code on the CPU-command level. It is known the x86 processors command system is redundant and allows the execution of the same ‘code’ using various different system commands. It breaks up the protected code into several processor commands or small command snippets and replace them by others, while maintaining the same end result. Thus the protector obfuscates the code not on the source level but on the level of the CPU commands.

The Code Morphing is multilevel technology containing hundreds of unique code transformation patterns. In addition this technology includes the special layer that transforms some commands into Virtual Machine commands (like P-Code). Code Morphing turns binary code into an undecipherable mess that is not similar to normal compiled code, and completely hides execution logic of the protected code.

There is no concept of code decryption with this system Protected code blocks are always in the executable state, and they are executed as a transformed code. The original code is completely lost and code restoration is an NP-hard problem.

The weak point of such scheme is that it significantly increases the size and affects the speed of a program. But protecting an application author usually doesn't need to transform its entire code. It is enough to protect only critical parts of your code, responsible for serial number verification, trial expiration date, and other evaluation restrictions. The rest of application code remains intact and software execution speed remains the same.


Below is a code sample generated by Delphi and a partial (the full listing contains over 500 instructions) listing of the transformed code.

Source code :

writeln('Test OK');

After compilation

mov eax, [$ 004092ec]
mov edx, $00408db4
call @WriteOLString
call @WriteLn
call @_IOTest

After the code transformation (partial):

db 3
add al, $30
xlat
call +$000025b2
jmp +$00000eec
call +$00000941
or al, $4a
scasd
call -$304ffbe9
rol eax, $14
mov edi, [ebx]
jmp +$00001738
mov ebx, eax
shr ebx, $03
push ebx
jmp +$0001b5e
call -$000001eb
jmp +$00003203
jmp +$00005df8
call +$00000910
adc dh, ah
fmul st(7)
adc [eax], al
les eax, [ecx+$0118bfc0]
stosb

http://www.strongbit.com "