How severe is CVE-2021-31755?

CVE-2021-31755 has a CVSS 3.1 base score of 9.8 (CRITICAL). EPSS estimates a 86.5% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-31755: Tenda AC11 Router Stack Buffer Overflow Vulnerability

CISA Known Exploited Vulnerabilities

Tenda AC11 Router Stack Buffer Overflow Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2021-11-03

Remediation due

2021-11-17

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-31755

Description

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.

Severity

CVSS 3.1 · CISA9.8 CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

SSVC · CISA-ADP

Exploitationactive

Automatableyes

Technical impacttotal

Affected Products

Vendor	Product	Affected versions
-	-	n/a

References

1 Links

Other references

https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3

Record Details

Published

2021-05-07

Last updated

2025-10-21

Assigner (CNA)

mitre

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.