VDB-343369 · CVE-2026-23566 · CNNVD-202601-4958

TeamViewer DEX Client up to 26.0 on Windows Content Distribution Service NomadBranch.exe input validation

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.
5.8	$0-$5k	0.00

Summaryinfo

A vulnerability was found in TeamViewer DEX Client up to 26.0 on Windows. It has been classified as problematic. This issue affects some unknown processing of the file NomadBranch.exe of the component Content Distribution Service. This manipulation causes input validation. The identification of this vulnerability is CVE-2026-23566. The attack needs to be done within the local network. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in TeamViewer DEX Client up to 26.0 on Windows. Affected by this vulnerability is an unknown code block of the file NomadBranch.exe of the component Content Distribution Service. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect integrity, and availability. The summary by CVE is:

A vulnerability in TeamViewer DEX Client (former 1E Client) - Content Distribution Service (NomadBranch.exe) prior version 26.1 for Windows allows an attacker on the adjacent network to inject, tamper with, or forge log entries in \Nomad Branch.log via crafted data sent to the UDP network handler. This can impact log integrity and nonrepudiation.

The weakness was shared with Bank of America. The advisory is shared at teamviewer.com. This vulnerability is known as CVE-2026-23566 since 01/14/2026. The exploitation appears to be easy. Access to the local network is required for this attack. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

Upgrading to version 26.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CNNVD (CNNVD-202601-4958). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

TeamViewer

Name

DEX Client

Version

26.0

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector: 🔒

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: Input validation
CWE: CWE-20
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: DEX Client 26.1

Timelineinfo

01/14/2026 CVE reserved
01/29/2026 +15 days Advisory disclosed
01/29/2026 +0 days VulDB entry created
02/01/2026 +3 days VulDB entry last update

Sourcesinfo

Advisory: teamviewer.com
Organization: Bank of America
Status: Confirmed

CVE: CVE-2026-23566 (🔒)
GCVE (CVE): GCVE-0-2026-23566
GCVE (VulDB): GCVE-100-343369
CNNVD: CNNVD-202601-4958 - TeamViewer DEX Client 安全漏洞

Entryinfo

Created: 01/29/2026 10:11
Updated: 02/01/2026 15:13
Changes: 01/29/2026 10:11 (65), 01/30/2026 17:33 (6), 01/31/2026 20:33 (1), 02/01/2026 15:13 (1)
Complete: 🔍
Cache ID: 216::103

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