VDB-343417 · Submit #740871 · CVE-2026-1638

Tenda AC21 1.1.1.1/1.dmzip/16.03.08.16 /goform/mDMZSetCfg dmzIp command injection

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.9	$0-$5k	0.69

Summaryinfo

A vulnerability marked as critical has been reported in Tenda AC21 1.1.1.1/1.dmzip/16.03.08.16. This affects the function mDMZSetCfg of the file /goform/mDMZSetCfg. This manipulation of the argument dmzIp causes command injection. This vulnerability is tracked as CVE-2026-1638. The attack is possible to be carried out remotely. Moreover, an exploit is present.

Detailsinfo

A vulnerability has been found in Tenda AC21 1.1.1.1/1.dmzip/16.03.08.16 and classified as critical. Affected by this vulnerability is the function mDMZSetCfg of the file /goform/mDMZSetCfg. The manipulation of the argument dmzIp with an unknown input leads to a command injection vulnerability. The CWE definition for the vulnerability is CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-1638. The exploitation appears to be easy. The attack can be launched remotely. Technical details and also a public exploit are known. MITRE ATT&CK project uses the attack technique T1202 for this issue.

It is possible to download the exploit at github.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202601-4966). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Router Operating System

Vendor

Tenda

Name

AC21

Version

License

commercial

Website

Vendor: https://www.tenda.com.cn/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔒

CNA Base Score: 6.3
CNA Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Command injection
CWE: CWE-77 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/29/2026 Advisory disclosed
01/29/2026 +0 days VulDB entry created
03/09/2026 +39 days VulDB entry last update

Sourcesinfo

Vendor: tenda.com.cn

Advisory: github.com
Status: Not defined

CVE: CVE-2026-1638 (🔒)
GCVE (CVE): GCVE-0-2026-1638
GCVE (VulDB): GCVE-100-343417
CNNVD: CNNVD-202601-4966 - Tenda AC21 命令注入漏洞

scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 01/29/2026 18:01
Updated: 03/09/2026 19:04
Changes: 01/29/2026 18:01 (57), 01/30/2026 05:07 (30), 01/30/2026 15:02 (6), 01/31/2026 20:13 (1), 02/01/2026 15:13 (1), 02/05/2026 05:52 (1), 03/09/2026 19:04 (11)
Complete: 🔍
Submitter: LX-LX
Cache ID: 216::103

Submitinfo

Accepted

Submit #740871: Tenda AC21 V16.03.08.16 Command Injection (by LX-LX)

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.