I've detected some defects on legacy third party assemblies that we're using on our code decompilind them. I would like to fix them but as I don't have the source code I need to directly modify the bytecode. The changes are really simple (changing an AND for an OR and NOPing some lines).
Is there an editor to do this kind of things? Doing the work with an hex editor would be the last option, I would preffer to have a hint of what instructions I have around the cursor ...
I think what you are looking for is .NET Reflector with the Reflexil add-on. Take a look at the screenshots, it's pretty powerful and it can modify IL code at runtime. Reflector used to be free of charge, you might be able to get some older version somewhere.