Reverse engineering the obfuscated TikTok VM

This seems like quite a lot of work to hide the code. What would the legitimate reasons for this be? Because it looks like it would make the program less optimized and more complexity just leads to more errors.

I understand the desire to make it harder for bots, but 1) it doesn't seem to be effective and bots seem to be going a very different route 2) there's got to be better ways that are more effective. It's not like you're going to stop clones through this because clones can replicate by just seeing how things work and reverse engineer blackbox style.

A generous take would be that they have their own internal GUI tools that make it easier for non-programmers to set up visual elements in this. That was historically the reason to invent VMs like Flash. A less generous take would account for the enormous potential for hiding nefarious code inside such a thing, and account for the nature of the government which deployed it, and conclude that it was a national security / defense project disguised as a candy-coated trojan horse.

VM-based architectures are really common in the obfuscation space, which is why you have executable packers[1], JS packers[2] and bot management products[3][4] leveraging similar techniques.

As for why the obfuscation is needed: bot management products suffer from a fundamental weakness in that ultimately, all of them simply collect static data from the environment, therefore it would make much more sense to make the steps involved as difficult to reverse engineer as possible. Once that is done, all you need to do is slightly change the schematics of your script every few weeks and publish a new bundle, and you've got yourself a pretty unsubvertible* protection scheme.

Regarding the "trojan horse", I think someone is yet to show proof that it's a Javascript exploit.

(*Unsubvertible is obviously relative, but raising the cost the attack, from say, $0.01/1000 requests to $10/1000 requests would massively cut down on abuse.)

[1] https://vmpsoft.com/

[2] https://jscrambler.com/

[3] https://github.com/neuroradiology/InsideReCaptcha

[4] https://www.zenrows.com/blog/bypass-cloudflare#_qEu5MvVdnILJ...

> Packers and obfuscators are not a "VM". It may look like a VM and act like a VM, in that it has opcodes that you can write to in another higher-level "language", but that is not a VM. It's in the same sandbox as the thing you're trying to obfuscate.

Indignant, caustic comments that simply discard all presented evidence such as this is the primary reason why people with the relevant experience have reduced their contributions on HN. I suspect I'll join their ranks too.