MPRESS versus UPX

[JoeWinograd]

Hi Folks,

For the past several years, I've done all of my custom software development (on W7 Pro 64-bit) for my clients with AutoHotkey. I always use the current V1 release and compile into an EXE with the standard compiler (usually 32-bit only, sometimes both 32-bit and 64-bit). I then use NSIS (Nullsoft) to create an installer (Setup32.exe and/or Setup64.exe), which is what the client gets.

I've been using MPRESS when compiling. The latest release is Version 2.19, dated 2-Jan-2012. Thanks to a post here by jNizM, I became aware that UPX development has resumed and there are now both 32-bit and 64-bit releases of Version 3.95, dated 26-Aug-2018.

I'm looking for opinions on MPRESS versus UPX. I'll appreciate comments on any and all aspects, but one specific issue that concerns me is malware/virus false positives on the compressed EXE — have you seen any difference between MPRESS and UPX on that front? Thanks, much Joe

[vvhitevvizard]

I'm looking for opinions on MPRESS versus UPX

UPX with command line options --ultra-brute --compress-icons=0 --nrv2d --crp-ms=999999 has better compression ratio but very slow.
Majority of my files r manually compressed but it requires to check every compressed file - some cease to work.

MPRESS-processed files r less prone to bugs after compression. But MPRESS x64 has some issues with x86 executables on x64 systems. So I use MPRESS x64 to compress x64 and MPRESS x86 to compress x86 ones.

issue that concerns me is malware/virus false positives on the compressed EXE

I experienced some issues long time ago last time. Everything is all right currently.

[JoeWinograd]

some cease to work

That definitely concerns me. In seven years of using the 2-Jan-2012 MPRESS release, I've never had the EXE file that it compresses cease to work.

So I use MPRESS x64 to compress x64 and MPRESS x86 to compress x86 ones.

I wasn't aware that MPRESS has separate 32-bit and 64-bit versions. The download that I use is a ZIP file with just one EXE in it that I think is both x86/x64-capable. Where are you getting separate mpress.exe files for 32-bit and 64-bit?

I experienced some issues long time ago last time. Everything is all right currently.

Good to hear!

Thanks, Joe

[SOTE]

UPX is "safer" or less likely to cause virus alerts and false positives, because it's more well known and anti-virus and anti-malware companies are more likely to have an unpacker for UPX. Another point is that anti-virus and anti-malware companies also seem to check if there is no version info, combined with compression/packer. The more "exotic" and less well known the compression/packer used, arguably the more likely it will trigger alerts and possible false positives.

[JoeWinograd]

Hi SOTE,
Thanks for the comments...very helpful! Regards, Joe

[vvhitevvizard]

I've never had the EXE file that it compresses cease to work.

yeah. very true. bit UPX can tackle more executable types.

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Where are you getting separate mpress.exe files for 32-bit and 64-bit?

I have x64 mpress 2.19 and x86 mpress 2.18. Cant provide u the download links tho.

[JoeWinograd]

UPX can tackle more executable types

Good to know, although I'm interested only in the EXE files created by the AutoHotkey "compiler" (Ahk2Exe).

[SOTE]

UPX has 32-bit and 64-bit versions as well.

https://github.com/upx/upx/releases/tag/v3.95
(Various versions of UPX)

[JoeWinograd]

Thanks, SOTE, I had noted that in my original post, but there's one thing I'm unclear on with respect to its 64-bit version. Is it that the 64-bit upx.exe itself runs on only 64-bit systems or is it that the compressed file it creates runs on only 64-bit systems? Or both of those?

[vvhitevvizard]

Is it that the 64-bit upx.exe itself runs on only 64-bit systems or is it that the compressed file it creates runs on only 64-bit systems? Or both of those?

it creates a stub (loader that unpacks executable's segments into virtual memory). x86 UPX version can create a x64 loader unpacking x64 executables which works on 64bit systems as well. x64 UPX version creates a x86 loader for x86 executables respectively.
just x64 UPX compresses files a tad faster.

[JoeWinograd]

x86 UPX version can create a x64 loader unpacking x64 executables which works on 64bit systems as well. x64 UPX version creates a x86 loader for x86 executables respectively.

Got it! So, other than speed, it doesn't matter whether I use 32-bit or 64-bit UPX to compress my 32-bit and 64-bit AHK EXE files. Thanks!

[Pankadai5]

Hi Folks,

For the past several years, I've done all of my custom software development (on W7 Pro 64-bit) for my clients with AutoHotkey. I always use the current V1 release and compile into an EXE with the standard compiler (usually 32-bit only, sometimes both 32-bit and 64-bit). I then use NSIS (Nullsoft) to create an installer (Setup32.exe and/or Setup64.exe), which is what the client gets.

I've been using MPRESS Broken Link for safety when compiling. The latest release is Version 2.19, dated 2-Jan-2012. Thanks to a post here by jNizM, I became aware that [url=https upx.github.io /]UPX[/url] Broken Link for safety development has resumed and there are now both 32-bit and 64-bit releases of Version 3.95, dated 26-Aug-2018.

I'm looking for opinions on MPRESS versus UPX. I'll appreciate comments on any and all aspects, but one specific issue that concerns me is malware/virus false positives on the compressed EXE — have you seen any difference between MPRESS and UPX on that front? Thanks, much Joe

Could you help me by creating a script that checks the computer's HWID so it can run?

[JoeWinograd]

Could you help me by creating a script that checks the computer's HWID so it can run?

By HWID, I presume that you mean a hardware identifier that is unique to each computer. If so, I'm not aware of anything that works universally. Some folks create a so-called "machine fingerprint" that attemps to identify a computer. Some of the fields used for that are variables built into AutoHotkey, such as A_ComputerName, A_IPAddress1, A_IPAddress2, A_IPAddress3, A_IPAddress4, A_Is64bitOS, A_Language, A_OSVersion, and A_UserName. Other fields sometimes used are the public IP address and various Win32 components, such as IdentifyingNumber, SerialNumber, ProcessorId, and UUID. But, again, none of that works universally. Regards, Joe