Unable to apply changes to AST

[ajmeese7]

Hello, when running this tool on my obfuscated JavaScript sample, I encounter the following issue:

$ npx restringer ./crypto_deobfuscated_manual.js                          
[+] Obfuscation type is augmented_proxied_array_function_replacements
[+] ==> Cycle 1 completed in 0.065 seconds with no changes (322838 nodes)
	[+] resolveFunctionToArray committed 1 new changes!
[+] ==> Cycle 2 completed in 21.652 seconds with 1 changes (322827 nodes)
	[+] removeRedundantBlockStatements committed 11 new changes!
	[+] resolveProxyVariables committed 38 new changes!
	[+] resolveProxyReferences committed 1021 new changes!
	[+] replaceIdentifierWithFixedAssignedValue committed 5 new changes!
	[+] simplifyCalls committed 32 new changes!
	[+] unwrapIIFEs committed 1 new changes!
[+] Applying changes to the root node...
[+] ==> Cycle 3 completed in 56.787 seconds with 1108 changes (328524 nodes)
	[+] resolveProxyReferences committed 34 new changes!
[+] ==> Cycle 4 completed in 11.028 seconds with 1142 changes (329008 nodes)
[+] ==> Cycle 5 completed in 1.089 seconds with 1142 changes (329008 nodes)
	[+] resolveMinimalAlphabet committed 4436 new changes!
	[+] resolveDefiniteBinaryExpressions committed 2002 new changes!
	[+] resolveMemberExpressionsLocalReferences committed 3 new changes!
	[+] resolveDefiniteMemberExpressions committed 1 new changes!
	[+] resolveLocalCalls committed 2094 new changes!
[+] ==> Cycle 6 completed in 629.334 seconds with 8536 changes (284790 nodes)
	[+] resolveProxyVariables committed 7 new changes!
	[+] resolveDeterministicIfStatements committed 1 new changes!
	[+] replaceIdentifierWithFixedAssignedValue committed 10 new changes!
[-] Unable to apply changes to AST: TypeError: Cannot read properties of undefined (reading '0')
[+] ==> Cycle 7 completed in 17.126 seconds with 18 changes (284788 nodes)
	[+] removeRedundantBlockStatements committed 1 new changes!
[-] Unable to apply changes to AST: TypeError: Cannot read properties of undefined (reading '0')
	[+] resolveProxyVariables committed 4 new changes!
[-] Unable to apply changes to AST: TypeError: Cannot read properties of undefined (reading '0')
[+] ==> Cycle 8 completed in 2.1 seconds with 23 changes (284788 nodes)
	[+] resolveMinimalAlphabet committed 264 new changes!
	[+] resolveDefiniteBinaryExpressions committed 68 new changes!

<--- Last few GCs --->


<--- JS stacktrace --->


#
# Fatal javascript OOM in MemoryChunk allocation failed during deserialization.
#

Trace/breakpoint trap (core dumped)

Is there any way this can be resolved, or a workaround I can implement on my end to allow the script to complete successfully? Even just failing gracefully and emitting the partially deobfuscated file before the errors would be great.

Thank you!

---

Possibly related: #64

[jorants]

Not a fix, but you could try using the -m 5 argument to limit the cycles to the first five.

[BenBaryoPX]

Thanks for reaching out @ajmeese7
I'll need the obfuscated JS file that this happens on so I can reproduce the issue before I can debug it.

[ajmeese7]

@BenBaryoPX the sample can be downloaded from here:

https://bazaar.abuse.ch/sample/f1bf8d22f9b6451e18564e2518ba6f40cb19128c8aaa86713bc4c43e01a2e7fd/