One Gadget
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Basic Information
One Gadget allows to obtain a shell instead of using system and "/bin/sh". One Gadget will find inside the libc library some way to obtain a shell (execve("/bin/sh")) using just one address.\
However, normally there are some constrains, the most common ones and easy to avoid are like [rsp+0x30] == NULL As you control the values inside the RSP you just have to send some more NULL values so the constrain is avoided.
To the address indicated by One Gadget you need to add the base address where libc is loaded.
[!TIP] One Gadget is a great help for Arbitrary Write 2 Exec techniques and might simplify ROP chains as you only need to call one address (and fulfill the requirements).
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