CVE-2021-31755
KEVTenda AC11 Router Stack Buffer Overflow Vulnerability
Description
Tenda AC11 devices contain a stack buffer overflow vulnerability in /goform/setmac which allows attackers to execute code via a crafted post request.
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 3.1 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HPublishedMay 7, 2021
Last modifiedJun 17, 2026
Added to KEVNov 3, 2021
Remediation dueNov 17, 2021
References
- github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3Broken LinkExploit
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755US Government Resource
0 recent articles mention this CVE
88
Risk assessment · Critical
Actively exploited. Patch immediately.
- Exploitation
- Confirmed in the wild (CISA KEV)
- Federal remediation deadline
- Overdue by 1805 days
- CVSS
- 9.8 CRITICAL
- EPSS (30-day exploit probability)
- 86.5% · top 1% of all CVEs
- Weakness
- CWE-787
- Attack vector
- Network, remotely reachable
- Preconditions
- No privileges and no user interaction
Recommended actions
- 1.Apply updates per vendor instructions.
- 2.Treat as emergency change: patch or isolate internet-facing instances first.
- 3.Review exposure: confirm which instances are reachable from the internet and restrict access until patched.
- 4.Hunt for compromise: review logs for the disclosure window, not just from the patch date.
Assessment is derived automatically from the live signals above; verify against your own asset inventory.