CVE-2021-46393: There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v10 variable is directly retrieved from the http request parameter startIp....

Summary

There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v10 variable is directly retrieved from the http request parameter startIp. Then v10 will be splice to stack by function sscanf without any security check,which causes stack over...

What to do

The CVE record does not list a fixed version. Check the vendor's site or the advisory links below - a fix may already be released.

Affected software

Vendor	Product	Affected versions
tenda	ax3_firmware	16.03.12.10 `cpe:2.3:o:tenda:ax3_firmware:16.03.12.10:::::::*`

Original advisory text

There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v10 variable is directly retrieved from the http request parameter startIp....

There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v10 variable is directly retrieved from the http request parameter startIp. Then v10 will be splice to stack by function sscanf without any security check,which causes stack overflow. By POSTing the page /goform/SetPptpServerCfg with proper startIp, the attacker can easily perform remote code execution with carefully crafted overflow data.

References

https://github.com/sec-bin/IoT-CVE/tree/main/Tenda/AX3/3 Exploit Third Party Advisory