VDB-369852 · CVE-2026-36823 · GCVE-0-2026-36823

Tenda W20E 15.11.0.6 HTTP formAddWebAuthUser webAuthUserInfo buffer overflow

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.
8.5	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical was found in Tenda W20E 15.11.0.6. Affected is the function formAddWebAuthUser of the component HTTP Handler. The manipulation of the argument webAuthUserInfo results in buffer overflow. This vulnerability is reported as CVE-2026-36823. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Tenda W20E 15.11.0.6. It has been classified as critical. Affected is the function formAddWebAuthUser of the component HTTP Handler. The manipulation of the argument webAuthUserInfo with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Shenzhen Tenda Technology Co., Ltd Tenda W20E v15.11.0.6 was discovered to contain a buffer overflow in the webAuthUserInfo parameter of the formAddWebAuthUser function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted HTTP request.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-36823 since 04/06/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/09/2026).

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

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Router Operating System

Vendor

Tenda

Name

W20E

Version

15.11.0.6

License

commercial

Website

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

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.5

VulDB Base Score: 8.8
VulDB Temp Score: 8.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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

04/06/2026 CVE reserved
06/09/2026 +64 days Advisory disclosed
06/09/2026 +0 days VulDB entry created
06/09/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: tenda.com.cn

Advisory: github.com
Status: Not defined

CVE: CVE-2026-36823 (🔒)
GCVE (CVE): GCVE-0-2026-36823
GCVE (VulDB): GCVE-100-369852

Entryinfo

Created: 06/09/2026 21:15
Changes: 06/09/2026 21:15 (56)
Complete: 🔍
Cache ID: 216::103