Critical severity · published Mar 4, 2022
CVE-2021-46393
There is a stack buffer overflow vulnerability in the formSetPPTPServer function of Tenda-AX3 router V16.03.12.10_CN
9.8
CVSS
15.9%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)15.9% · higher than 97% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AF
Ax3 Firmware · Tenda
16.03.12.10 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-46393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-46393
Exploit
https://github.com/sec-bin/IoT-CVE/tree/main/Tenda/AX3/3
More from Ax3 Firmware
9.8
CVE-2025-69764
Tenda AX3 firmware v16.03.12.11 contains a stack-based buffer overflow in the formGetIptv function due to improper handling of the stbpvid stack buffer, which may result in memory…
9.8
CVE-2025-69762
Tenda AX3 firmware v16.03.12.11 contains a stack overflow in formSetIptv via the list parameter, which can cause memory corruption and enable remote code execution
9.8
CVE-2025-69766
Tenda AX3 firmware v16.03.12.11 contains a stack-based buffer overflow in the formGetIptv function due to improper handling of the citytag stack buffer, which may result in memory…
9.8
CVE-2025-69763
Tenda AX3 firmware v16.03.12.11 contains a stack overflow in formSetIptv via the vlanId parameter, which can cause memory corruption and enable remote code execution
9.8
CVE-2023-51812
Tenda AX3 v16.03.12.11 was discovered to contain a remote code execution (RCE) vulnerability via the list parameter at /goform/SetNetControlList