Summary
- A buffer overflow vulnerability in VulnServer allows an attacker to overwrite the EIP.
- To exploit this, we first generate a unique pattern to overwrite the EIP.
- We then create a payload with msfvenom.
- We identify and remove any bad characters which cause our payload to crash.
- We then craft a shellcode and assemble it within our buffer.
- We add an extra NOP sled before our shellcode.
- Finally, we send the payload.
- With the ESP memory layout, we can identify the base address.
- This contains our shellcode.
- We remove any bad characters which cause our exploit to crash.
- We then craft a shellcode and assemble it within our buffer.
- We add an extra NOP sled before our shellcode.
- Finally, we send the payload.
- We then craft a shellcode and assemble it within our buffer.
- We add an extra NOP sled before our shellcode.
- Finally, we send the payload.
- We then craft a shellcode and assemble it within our buffer.
- We add an extra NOP sled before our shellcode.
By Febi Mudiyanto
Original Article