ILReplacer (.Net Patcher)

ILReplacer is a Patcher or simple tool to find and replace .Net application IL code instructions such as ldstr, ldc.i4, brfalse.s, etc.. It support managed and mixed mode assembly.

Currently, this tool only check if instructions operand is valid or not if the OpCode is Call else not checked.

Download

Download ILReplacer from Release page, the package also contains block file DemoTarget.ilr and DemoTarget.exe for testing.

Docs

The Blocks The blocks instruction format is like the following

OpCode operand
OpCode
=

The symbol = is used in Replace input, it mean do not change original Opcode and Operand.

BLocks Example:

Change App name for DemoTarget.exe from Demo App to Demo App || Cracked

In Find textbox add:

ldarg.0
ldstr "Demo App"

In Replace textbox add

ldarg.0
ldstr "Demo App || Cracked"

or use = to keep ldarg.0 unchanged

=
ldstr "Demo App || Cracked"

Multiple Blocks For replacing multiple blocks use the ======= (minimum 3 characters) as separator

ldarg.0
ldstr "Demo App"
===========
ldarg.0
ldstr Other String

Note: the double quote in operand is optional

Find Blocks If operand is not empty it will be used to compare with original operand, for example:

call badMethod

will search if Operand contains method name badMethod

Replace Blocks If the OpCode is a Call the operand have to be Hex number or MDToken like 0x06000001 or 06000001 and not method Name, example

call 0x06000001

To know MDToken for method you can use DnSpy

Save and Load Blocks You can save and load the blocks to file, just click the Menu on the top.

Screenshot

Credit

Thanks to @0xd4d for dnlib library.