CVE-2021-31755

An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. A stack buffer overflow vulnerability in /goform/setmac allows attackers to execute arbitrary code on the system via a crafted post request.

CVSS v3 9.8 CRITICAL
CVSS v2.0 10.0 HIGH

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

10.0^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:C/I:C/A:C

Exploitability : 10.0 / Impact : 10.0

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3	Broken Link Exploit Issue Tracking Third Party Advisory
https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3	Broken Link Exploit Issue Tracking Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755	US Government Resource

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:tenda:ac11_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:tenda:ac11:-:*:*:*:*:*:*:*

History

10 Nov 2025, 14:42

Type	Values Removed	Values Added
References	~~() https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755 -~~	() https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755 - US Government Resource

Information

Published : 2021-05-07 23:15

Updated : 2025-11-10 14:42

NVD link : CVE-2021-31755

Mitre link : CVE-2021-31755

CVE.ORG link : CVE-2021-31755

JSON object : View

Products Affected

tenda

ac11_firmware
ac11

CWE

CWE-787

Out-of-bounds Write

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