pwnmedium

New year party

grodno_new_year_2026

Task: Binary that allocates RWX memory via mmap, copies user input with strcpy, and executes it as code. Solution: Sent a null-byte-free execve("/bin//sh") shellcode that bypasses the strcpy null terminator restriction, obtained a shell, and ran /bin/newyear to get the flag.

$ ls tags/ techniques/
shellcodemmaprwxstrcpynull_free
shellcode_injectionrwx_memory_execution
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