CVE-2021-46394
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3...
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v13 variable is directly retrieved from the http request parameter startIp. Then v13 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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v13 variable is directly retrieved from the http request parameter startIp. Then v13 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.
- Record
CVE-2021-46394- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-787
- Updated
- 2026-11-02
CVE List No score
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v13 variable is directly retrieved from the http request parameter startIp. Then v13 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.
- Record
CVE-2021-46394- Updated
- 2026-11-02
EUVDEUVD-2021-33073 No score
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v13 variable is directly retrieved from the http request parameter startIp. Then v13 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.
- Record
EUVD-2021-33073- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-qgw7-h965-2gp6
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3...
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN. The v13 variable is directly retrieved from the http request parameter startIp. Then v13 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.
- Record
GHSA-qgw7-h965-2gp6- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-46394 is a critical vulnerability (CVSS 9.8) in Tenda Ax3 Firmware, published March 4, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.74%, the 86th percentile. No source names a fixed version.