Saurez-vous exploiter le binaire fourni et extraire le flag ?
nc challenges.ecsc-teamfrance.fr 4003
+ fichier armory sans extension
file armory
armory: ELF 32-bit LSB executable, ARM, EABI5 version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux.so.3, for GNU/Linux 3.2.0, BuildID[sha1]=aaa2d5ba6d3a6cf3958eb9073e673795c2f1e24e, not stripped
Comme on peut s'y attendre, s'agissant d'un fichier ARM, impossible de le lancer sur x86_64.
gdb ./armory
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Reading symbols from ./armory...(no debugging symbols found)...done.
(gdb) r
Starting program: /mnt/c/Users/didier/Documents/ANSSI-ECSC/armory
/bin/bash: /mnt/c/Users/didier/Documents/ANSSI-ECSC/armory: cannot execute binary file: Exec format error
/bin/bash: /mnt/c/Users/didier/Documents/ANSSI-ECSC/armory: Success
During startup program exited with code 126.
(gdb) q
Article intéressant : https://ownyourbits.com/2018/06/13/transparently-running-binaries-from-any-architecture-in-linux-with-qemu-and-binfmt_misc/
qemu-arm armory
/lib/ld-linux.so.3: No such file or directory
strings armory
/lib/ld-linux.so.3 libc.so.6 fflush __isoc99_scanf puts abort printf system __libc_start_main __gmon_start__ GLIBC_2.7 GLIBC_2.4 /bin/dash Hello, what's your name? Hello %s! GCC: (Debian 6.3.0-18) 6.3.0 20170516 aeabi /usr/lib/gcc-cross/arm-linux-gnueabi/6/../../../../arm-linux-gnueabi/lib/crt1.o /usr/lib/gcc-cross/arm-linux-gnueabi/6/../../../../arm-linux-gnueabi/lib/crti.o call_weak_fn /usr/lib/gcc-cross/arm-linux-gnueabi/6/../../../../arm-linux-gnueabi/lib/crtn.o crtstuff.c __JCR_LIST__ deregister_tm_clones __do_global_dtors_aux completed.9272 __do_global_dtors_aux_fini_array_entry frame_dummy __frame_dummy_init_array_entry chall.c elf-init.oS __FRAME_END__ __JCR_END__ __init_array_end _DYNAMIC __init_array_start _GLOBAL_OFFSET_TABLE_ __libc_csu_fini printf@@GLIBC_2.4 __bss_start__ fflush@@GLIBC_2.4 _edata __bss_end__ __data_start puts@@GLIBC_2.4 __libc_start_main@@GLIBC_2.4 system@@GLIBC_2.4 __gmon_start__ __dso_handle _IO_stdin_used __libc_csu_init __end__ __bss_start main __isoc99_scanf@@GLIBC_2.7 __TMC_END__ evil abort@@GLIBC_2.4 .symtab .strtab .shstrtab .interp .note.ABI-tag .note.gnu.build-id .gnu.hash .dynsym .dynstr .gnu.version .gnu.version_r .rel.dyn .rel.plt .init .text .fini .rodata .ARM.exidx .eh_frame .init_array .fini_array .jcr .dynamic .got .data .bss .comment .ARM.attributes