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Ropemporium x86_64 ret2csu

cdpointpoint — Thu, 08 Jun 2023 00:00:00 +0000

ret2csu Introduction As an introduction we can read we can read the description in the ropemporium site Same same, but different This challenge is very similar to “callme”, with the exception of the useful gadgets. Simply call the ret2win() function in the accompanying library with same arguments that you used to beat the “callme” challenge (ret2win(0xdeadbeef, 0xcafebabe, 0xd00df00d) for the ARM & MIPS binaries, ret2win(0xdeadbeefdeadbeef, 0xcafebabecafebabe, 0xd00df00dd00df00d) for the x86_64 binary.

Ropemporium x86_64 pivot

cdpointpoint — Wed, 07 Jun 2023 20:00:00 +0000

pivot Introduction With this exercice we have a limited space to put our chaine. We have to use this space as a first stage to prepare a second stage without limit. The first stage : use a reading function like gets to write the second staged rop chain a writable memory segment pivot : move the stack in this new segment The second stage : the hacking rop chaine. The reference challenge page from ropemporium site is here : pivot

Ropemporium x86_64 fluff

cdpointpoint — Tue, 06 Jun 2023 00:00:00 +0000

fluff Consigne Working backwards Once we’ve employed our usual drills of checking protections and searching for interesting symbols & strings, we can think about what we’re trying to acheive and plan our chain. A solid approach is to work backwards: we’ll need a write gadget - for example mov [reg], reg or something equivalent - to make the actual write, so we can start there. Do it! There’s not much more to this challenge, we just have to think about ways to move data into the registers we want to control.

Ropemporium x86_64 bad chars

cdpointpoint — Mon, 05 Jun 2023 00:00:00 +0000

bad chars Introduction The challenge is described on the ropemporium site : https://ropemporium.com/challenge/badchars.html with some useful indications. The good, the bad Dealing with bad characters is frequently necessary in exploit development, you’ve probably had to deal with them before while encoding shellcode. “Badchars” are the reason that encoders such as shikata-ga-nai exist. When constructing your ROP chain remember that the badchars apply to every character you use, not just parameters but addresses too.

Ropemporium x86_64 write4

cdpointpoint — Sun, 04 Jun 2023 00:00:00 +0000

write4 Description Things have been rearranged a little for this challenge; the printing logic has been moved into a separate library in an attempt to mitigate the alternate solution that is possible in the callme challenge. The stack smash also takes place in a function within that library, but don’t worry this will have no effect on your ROP chain. Important! A PLT entry for a function named print_file() exists within the challenge binary, simply call it with the name of a file you wish to read (like “flag.

Ropemporium x86_64 callme

cdpointpoint — Sat, 03 Jun 2023 00:00:00 +0000

callme Introduction Cette fois-ci on doit appeler trois fonctions successivement avec des paramètres attendus. Découverte gef➤ disas usefulFunction Dump of assembler code for function usefulFunction: 0x00000000004008f2 <+0>: push rbp 0x00000000004008f3 <+1>: mov rbp,rsp 0x00000000004008f6 <+4>: mov edx,0x6 0x00000000004008fb <+9>: mov esi,0x5 0x0000000000400900 <+14>: mov edi,0x4 0x0000000000400905 <+19>: call 0x4006f0 0x000000000040090a <+24>: mov edx,0x6 0x000000000040090f <+29>: mov esi,0x5 0x0000000000400914 <+34>: mov edi,0x4 0x0000000000400919 <+39>: call 0x400740 0x000000000040091e <+44>: mov edx,0x6 0x0000000000400923 <+49>: mov esi,0x5 0x0000000000400928 <+54>: mov edi,0x4 0x000000000040092d <+59>: call 0x400720 0x0000000000400932 <+64>: mov edi,0x1 0x0000000000400937 <+69>: call 0x400750 End of assembler dump.

Ropemporium x86_64 split

cdpointpoint — Fri, 02 Jun 2023 00:00:00 +0000

Introduction Dans ce second exercice on doit passer un argument à la fonction appelée. L’argument est présent dans le programme. Découverte Exécution $ ./split split by ROP Emporium x86_64 Contriving a reason to ask user for data... > AAAAAAA Thank you! Exiting Exploration du code La fonction main : gef➤ disas main Dump of assembler code for function main: 0x0000000000400697 <+0>: push rbp 0x0000000000400698 <+1>: mov rbp,rsp 0x000000000040069b <+4>: mov rax,QWORD PTR [rip+0x2009d6] # 0x601078

Ropemporium x86_64 ret2win

cdpointpoint — Thu, 01 Jun 2023 00:00:00 +0000

ret2win Introduction Ce premier exercice jette les bases de l’exploitation d’un débordement de pile avec une pile non exécutable. L’exploitation la plus simple consiste à appeler une fonction existante. Dans ce premier exercice la fonction présente dans le code et ne demande pas de paramètre. On va décrire la démarche d’évaluation de la taille du débordement qui sera considérée comme acquise dans les autres exercices. Découverte Lancement du programme :