---- Writeup ----CTF: BACKDOOR 2014Problem: binary-10Author: Dr.OptixAll rights reserved.-----------------I will start with basic recon.$ file bin10 bin10: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.24, BuildID[sha1]=e0f10986e9a0fc976ff2be10b411f368bfd53700, not stripped$ strings bin10 /lib64/ld-linux-x86-64.so.2CyIklibstdc++.so.6__gmon_start___Jv_RegisterClassespthread_cancel_ZNSsD1Ev_ZNSt8ios_base4InitD1Ev_ZNSsC1EPKcRKSaIcE_ZNKSs7compareEPKc_ZNSaIcEC1Ev_ZSt3cin_ZStrsIcSt11char_traitsIcESaIcEERSt13basic_istreamIT_T0_ES7_RSbIS4_S5_T1_E__gxx_personality_v0_ZSt4cout_ZStlsISt11char_traitsIcEERSt13basic_ostreamIcT_ES5_PKc_ZSt4endlIcSt11char_traitsIcEERSt13basic_ostreamIT_T0_ES6__ZNSaIcED1Ev_ZNSsC1Ev_ZNSolsEPFRSoS_E_ZStlsIcSt11char_traitsIcESaIcEERSt13basic_ostreamIT_T0_ES7_RKSbIS4_S5_T1_E_ZNSt8ios_base4InitC1Evlibgcc_s.so.1_Unwind_Resumelibc.so.6__cxa_atexit__libc_start_mainGCC_3.0GLIBC_2.2.5CXXABI_1.3GLIBCXX_3.4fff.l$ Lt$(L|$0H40511702a6193f9b38d37699e676fd40Enter the password: a_few_basic_skills_will_doThe flag for this level is That doesn't seem to be the correct password.Access Denied.;*3$"zPLRThis looks like a potential flag: 40511702a6193f9b38d37699e676fd40Bingo! Flag is indeed: 40511702a6193f9b38d37699e676fd40~ Q.E.D