CVE Tools
Sign in

CVE-2021-31755

Published: May 7, 2021Updated: Nov 10, 2025 Sources: CVE List NVD BDUCWE-787
9.8CRITICAL
NVD MITRE
EPSS Score
85.8%
Top 0.3%
CISA KEV
Active Exploitation
Since Nov 3, 2021
Exploits
1 Known
Remediation
Patch Available
Self-Check
Nuclei

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-787

Affected Products

tenda
commercial·CN
ac11 firmware
Networking Infrastructure
Shenzhen Tenda Technology Co., Ltd.
commercial·CNaka tenda
Tenda AC11On-premNetwork Device
Networking Infrastructure / router-switch
and 1 more affected products View all →

Exploitability

CISA Known Exploited Vulnerability
Added to KEV:Nov 3, 2021
Remediation due:Nov 17, 2021

Required action: Apply updates per vendor instructions.

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available
Is your org exposed to CVE-2021-31755?We'll check your whole external perimeter for exposure — free. Check my exposure

Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

2 techniques
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3
github.com
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-31755
cisa.gov
https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3
github.com
and 3 more references View all →
News mentions
1

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2021-31755 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows