The fascinating process of reverse engineering this VM is detailed here.

TikTok uses a custom virtual machine (VM) as part of its obfuscation and security layers. This project includes tools to:

Deobfuscate webmssdk.js that has the virtual machine.

Decompile TikTok’s virtual machine instructions into readable form.

Script Inject Replace webmssdk.js with the deobfuscated VM injector.

Sign URLs Generate signed URLs which can be used to perform auth-based requests eg. Post comments.