Amelie Lacroix

System Hacking ( pwnable ) 검색 결과

해당 글 83건

[Layer7 CTF] Angel-in-us ( write-up )

Layer7 CTF - Angel in usSummaryTop chunk freestdout leakscanf trick이문제는 SED팀 소속 Howdays라는 빡고수형이 낸 문제이다.대회중에도 솔버가 한명도 없었던 재밌는 문제이다. Analysismain()void __fastcall __noreturn main(__int64 a1, char **a2, char **a3) { __int16 buf; // [rsp+6h] [rbp-Ah] unsigned __int64 canary; // [rsp+8h] [rbp-8h] ​ canary = __readfsqword(0x28u); setup(); buf = 0; while ( 1 ) { menu(); read(0, &buf, 2uLL); if ( buf ==..

System Hacking ( pwnable )/CTF Write-up 2019. 10. 11. 15:37

[Layer7 CTF] How old are you? ( write-up )

Layer7 CTF - How old are you?Summarysimple trickseccomp syscallopenat()다른 출제자분들이 문제를 너무 빡시게내셔서 나도 빡시게 내야하나 싶었다.근데 그냥 쉬운문제 하나 있어야겠다 싶어서 쉬운거 하나 냈다.원래 getdents함수를 이용해서 플래그 패스를 찾게 하려고 했으나 그냥 쉽게 냈다. Analysismain()int __cdecl main(int argc, const char **argv, const char **envp) { char buf; // [rsp+0h] [rbp-110h] int v5; // [rsp+100h] [rbp-10h] int v6; // [rsp+104h] [rbp-Ch] int v7; // [rsp+108h] [rbp-..

System Hacking ( pwnable )/CTF Write-up 2019. 10. 11. 12:34

[pwnable.tw] babystack ( write-up )

pwnable.tw babystack ( 250pts )Mitigation[*] '/home/juntae/wargame/pwnable.tw/babystack/babystack' Arch: amd64-64-little RELRO: Full RELRO Stack: Canary found NX: NX enabled PIE: PIE enabled FORTIFY: Enabled매우 빡치게 미티게이션이 다걸려있습니다.여기서 카나리는 __stack_check_fail함수를 사용하기때문에 걸려있습니다.checksec에서는 해당 함수를 사용하면 카나리가 있다고 판단하나봐요. Analysismain()__int64 __fastcall main(__int64 a1, char **a2, char **a3) { _QWORD *..

System Hacking ( pwnable )/pwnable.TW Write-up 2019. 10. 2. 13:18

[pwnable.tw] seethefile ( write-up )

Pwnable.tw seethefile ( 250 pts )Summary/proc/self/mapsFSOPFake IO_file Analysismain에서는 open / read / write / close / exit 총 5개의 기능을 한다. openfile()int openfile() { int result; // eax ​ if ( fp ) { puts("You need to close the file first"); result = 0; } else { memset(magicbuf, 0, 0x190u); printf("What do you want to see :"); __isoc99_scanf("%63s", filename); if ( strstr(filename, "flag") ) { puts..

System Hacking ( pwnable )/pwnable.TW Write-up 2019. 9. 24. 16:24

[Timisoara CTF] Timisoara CTF Quals ( write-up )

Crypto - solved by team comflexBaby Crypto ( 50 pts )In the name of the problem, I thought it was a Caesar cipher.So I use Caesar decoder site. ( https://cryptii.com/ )Shift by 8 to get the flag.Otil bw amm gwc uilm qb! Emtkwum bw bpm ewvlmznct ewztl wn kzgxbwozixpg! Pmzm qa gwcz zmeizl: BQUKBN{Rctqca_Kimaiz_e0ctl_j3_xzwcl} ​ => Glad to see you made it! Welcome to the wonderful world of cryptogr..

System Hacking ( pwnable )/CTF Write-up 2019. 9. 22. 14:39