CVE-2021-31755Actively exploitedAdded to KEV 2021-11-03

Tenda AC11 Router Stack Buffer Overflow Vulnerability

Tenda, AC11 Router

Description

Tenda AC11 devices contain a stack buffer overflow vulnerability in /goform/setmac which allows attackers to execute code via a crafted post request.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

86.5%

estimated chance of real-world exploitation in the next 30 days, higher than 99.7% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

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