No Operation (NOP) Sled If you are using a direct address when injecting code, you will be left with the burden of guessing exactly where your payload is located in memory, which is next to impossible.The problem is that your payload will not always be in the exact same place. Under UNIX, it is common that the same software package is recompiled on different systems, different compilers, and different optimization settings. What works on one copy of the software might not work on another. Therefore, to minimize this effect and decrease the required precision of a smash, we use the no operation (NOP) sled. The idea is simple.A NOP is an instruction that does nothing; it only takes up space. (Incidentally, the NOP was originally created for debugging.) Since the NOP is only a single byte long, it is immune to the problems of byte ordering and alignment issues. Figure 5.9

No Operation (NOP) Sled If you are using a direct address when injecting code, you will be left with the burden of guessing exactly where your payload is located in memory, which is next to impossible.The problem is that your payload will not always be in the exact same place. Under UNIX, it is common that the same software package is recompiled on different systems, different compilers, and different optimization settings. What works on one copy of the software might not work on another. Therefore, to minimize this effect and decrease the required precision of a smash, we use the no operation (NOP) sled. The idea is simple.A NOP is an instruction that does nothing; it only takes up space. (Incidentally, the NOP was originally created for debugging.) Since the NOP is only a single byte long, it is immune to the problems of byte ordering and alignment issues. Figure 5.9

Microsoft Visual C#

7th Edition

ISBN:9781337102100

Author:Joyce, Farrell.

Publisher:Joyce, Farrell.

Chapter8: Advanced Method Concepts

Section: Chapter Questions

Problem 7RQ

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The word "buffer overflow" needs to be defined.