![]() ![]() However, a preliminary analysis suggests that an attacker-controlled controller may be able to reduce the expiration time of existing domains due to an integer overflow in the renew function. According to the documentation, controllers are allowed to register new domains and extend the expiry of existing domains, but they cannot change the ownership or reduce the expiration time of existing domains. The NUL terminator could have been included in the first of the two pushed constants, eliminating the need for the first push %eax.Ethereum Name Service (ENS) is a distributed, open, and extensible naming system based on the Ethereum blockchain. Odd that there are 2 slashes in the filename. Buffer overflow vulnerability code#The code is essentially doing: char filename = "/bin//sh" ![]() It is likely that $ebp has a different value when running in stack.c, which causes execution to jump to garbage. You need to get the value that $ebp will be when it's in bof in stack.c. If this is the case, then the value of $ebp in exploit.c is meaningless. ![]() Is that dump from running exploit.c or stack.c? The fact that there's a NUL byte in the dump at 0xbffff180 implies that this is exploit.c, because the strcpy in stack.c would have stopped copying at the NUL byte. UPDATE: The memory is part of stack.c after I enter bof and copy the string. Why does this happen and why do the NOPs at the end of the overflowing buffer not get replaced by 0x0s? Yet when I run it, I get a segmentation fault. * Save the contents to the file "badfile" */ *(buffer+i) = 0x0 // end the string with nul characters Memcpy(buffer+128, shellcode, sizeof(shellcode)) // copy the shellcodeįor(i = 128+sizeof(shellcode) i < SIZE i++) *(ptr+i) = EBP+64 // this is the jump spot * You need to fill the buffer with appropriate contents here */ * Initialize buffer with 0x90 (NOP instruction) */ The problem is I keep getting segmentation faults, even though the memory layout looks correct. I am trying to fill it with a 517 byte buffer which I put into badfile. * The following statement has a buffer overflow problem */ * Our task is to exploit this vulnerability */ * This program has a buffer overflow vulnerability. I was doing the SEED lab on buffer overflows which has the following vulnerable code: /* stack.c */ ![]()
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