A note regarding my Po C: With a (hopefully) successful file modification, one should get a messagbox saying: If you don't have the necessary file access rights, the Create File function will fail and program will just silently terminate.Until that has been solved, you must grant yourself the necessary rights before launching the program.Holy crap I just noticed that you can make the tampered executable run properly too, with signature valid!!!!!To do so you must also adjust the size of the certificate as given inside the certificate itself. I'll update the first post with a 4'th step. You can hide porn images inside microsoft signed system files, and the digital signature is still valid, as well as the executable working just fine. For those unfamiliar with the stuff; Here's a nice and easy (and free) PE editor to use; In addition, a separate program is included to extract the hidden data.There's more information in the included readme.
In the meantime take Auto It compiled scripts as an example.
One would expect that an executable that is signed with a digital certificate, should be impossible to tamper with without invalidating the certificate. Actually, when thinking about it, it may not be surprising given the design of Portable Executables.
But it still bothers me that this should be possible.
Answer: The best guess is 5 hours, but it depends on your release of Oracle.
When you are testing changes to SQL performance (in a test environment), you can always to an "The landmark book "Advanced Oracle SQL Tuning The Definitive Reference" is filled with valuable information on Oracle SQL Tuning.
Search for not invalidating:
I have tested on both architectures and modified the kernel (ntoskrnl.exe) to contain some garbage data.