I've been trying to solve this challenge for some time but I've ran out of ideas. The elf x86-64 binary is position independent so I can't predict or bruteforce the addresses of the gadgets needed for ROP or stack juggling since there is no information leak, Even though the stack is executable I didn't find any way to redirect the execution to some useful address on the stack. What am I missing?

tehron

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RE: Dead end?
Aug 21, 2023 - 22:13:18 (3y 70d) Google/translate1Thank You!1Good Post!0Bad Post! link

The challenge hasn't been solved since the server move, so it might be broken -- haven't checked tho.
Can anyone confirm if it is working (or not)?

Judicael

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RE: Dead end?
Jan 19, 2024 - 14:46:56 (2y 284d) Google/translate1Thank You!1Good Post!0Bad Post! link

Quote from cyberrac
Aug 18, 2023 - 06:10:58

I've been trying to solve this challenge for some time but I've ran out of ideas. The elf x86-64 binary is position independent so I can't predict or bruteforce the addresses of the gadgets needed for ROP or stack juggling since there is no information leak, Even though the stack is executable I didn't find any way to redirect the execution to some useful address on the stack. What am I missing?

tehron

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RE: Dead end?
Jan 26, 2024 - 15:04:45 (2y 277d) Google/translate1Thank You!2Good Post!0Bad Post! link

We changed the challenge a bit to reflect the behavior of the original binary. This also gives as the opportunity for a sequel. ;)
Happy challenging!

tehron

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RE: Dead end?
Mar 18, 2025 - 23:44:41 (1y 225d) Google/translate1Thank You!1Good Post!0Bad Post! link

Restored the original binary for the challenge.

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