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I have tried all the I have learned so far to figure out how to deal with this instance of obfuscation. enter image description here

So far I understand that an opaque predicate is present, causing an unconditional jump to one byte into L0.

What I don't understand is how to deal with this issue in IDA. If the jump is made to L0+1 how can I mark the byte E8 as data, or deal with this otherwise.

Any help would be appreciated. Thanks.

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IDA is good at recognising such tricks, but if it didn't you can press D having the call instruction selected.

This will convert the opcode to a data, displaying just bunch of dbs. After that, select the byte that has db 58 (so one after E8) and press C to convert it to code again without the first byte.

Result after the changes.

enter image description here

I don't know if this could be automated - probably with some script that IDA supports it could be.

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