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Common Errors

isolated-vm

If you see errors like

  • isolated_vm.node: undefined symbol: _ZNK2v815ValueSerializer8Delegate20SupportsSharedValuesEv
  • ERR_DLOPEN_FAILED
  • Segmentation fault

it most likely means that the isolated-vm package was built against a different version of Node.js than the one you are using. This can happen if you upgrade Node.js after installing webcrack.

To fix this, run npm rebuild isolated-vm in your project directory or delete the node_modules/isolated-vm directory and run npm install again.

For Node 20.x and above, disabling snapshots may be necessary:

sh
set NODE_OPTIONS=--no-node-snapshot
webcrack input.js
sh
NODE_OPTIONS=--no-node-snapshot webcrack input.js

or

sh
node --no-node-snapshot your-script.js

For any other issues, please refer to the isolated-vm readme.

Heap Out Of Memory

FATAL ERROR: Ineffective mark-compacts near heap limit Allocation failed - JavaScript heap out of memory

Fix by running node with the --max-old-space-size flag. For example:

sh
set NODE_OPTIONS=--max-old-space-size=8192
webcrack bundle.js
sh
NODE_OPTIONS="--max-old-space-size=8192" webcrack bundle.js

or

sh
node --max-old-space-size=8192 your-script.js

__DECODE_0__

If this appears in your code, the deobfuscator failed to decode a string from the string array. This can happen in forked javascript-obfuscator versions or when Dead Code Injection is enabled.

Open an issue if you encounter this.