Medium severity · published Sep 5, 2023
CVE-2021-40546
Tenda AC6 US_AC6V4.0RTL_V02.03.01.26_cn.bin allows attackers (who have the administrator password) to cause a denial of service (device crash) via a long string in the wifiPwd_5G…
4.9
CVSS
0.7%
EPSS
No
On KEV
Description
Tenda AC6 US_AC6V4.0RTL_V02.03.01.26_cn.bin allows attackers (who have the administrator password) to cause a denial of service (device crash) via a long string in the wifiPwd_5G parameter to /goform/setWifi.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AF
Ac6 Firmware · Tenda
02.03.01.26 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-40546
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-40546
Exploit
https://github.com/doudoudedi/buffer_overflow/blob/main/Tenda%20AC6%20V4.0-Denial%20of%20Service%20Vulnerability.md
More from Ac6 Firmware
9.8
CVE-2026-8263
Tenda AC6 httpd WifiExtraSet fromSetWirelessRepeat os command injection
9.8
CVE-2025-52221
Tenda AC6 15.03.05.16_multi is vulnerable to Buffer Overflow in the formSetCfm function via the funcname, funcpara1, and funcpara2 parameters
9.8
CVE-2025-31355
A firmware update vulnerability exists in the Firmware Signature Validation functionality of Tenda AC6 V5.0 V02.03.01.110
9.8
CVE-2025-24322
An unsafe default authentication vulnerability exists in the Initial Setup Authentication functionality of Tenda AC6 V5.0 V02.03.01.110
9.8
CVE-2025-27129
An authentication bypass vulnerability exists in the HTTP authentication functionality of Tenda AC6 V5.0 V02.03.01.110