CODESYS Visualization 4.2.0.0/4.8.0.0 Concurrent Login insufficiently protected credentials

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.
4.1$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in CODESYS Visualization. This vulnerability affects unknown code of the component Concurrent Login. The manipulation results in insufficiently protected credentials. This vulnerability is identified as CVE-2026-0393. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, was found in CODESYS Visualization. Affected is an unknown functionality of the component Concurrent Login. The manipulation with an unknown input leads to a insufficiently protected credentials vulnerability. CWE is classifying the issue as CWE-522. The product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval. This is going to have an impact on confidentiality. CVE summarizes:

The affected product may expose credentials remotely between low privileged visualization users during concurrent login operations due to insufficient isolation of authentication data. The vulnerability affects only login operations within an active visualization session.

The weakness was released by Silvan Schweizer as vde-2026-052. The advisory is shared for download at codesys.csaf-tp.certvde.com. This vulnerability is traded as CVE-2026-0393 since 11/27/2025. The exploitability is told to be easy. It is possible to launch the attack remotely. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1552.

Upgrading to version 4.10.0.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1619). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

  • CODESYS CODESYS

Productinfo

Vendor

Name

Version

License

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: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

Exploitinginfo

Class: Insufficiently protected credentials
CWE: CWE-522
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Visualization 4.10.0.0

Timelineinfo

11/27/2025 CVE reserved
05/21/2026 +174 days Advisory disclosed
05/21/2026 +0 days VulDB entry created
05/22/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: vde-2026-052
Researcher: Silvan Schweizer
Status: Confirmed

CVE: CVE-2026-0393 (🔒)
GCVE (CVE): GCVE-0-2026-0393
GCVE (VulDB): GCVE-100-365016
CERT Bund: WID-SEC-2026-1619 - CODESYS: Schwachstelle ermöglicht Offenlegung von Informationen

Entryinfo

Created: 05/21/2026 15:26
Updated: 05/22/2026 05:09
Changes: 05/21/2026 15:26 (68), 05/22/2026 05:09 (7)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you want to use VulDB in your project?

Use the official API to access entries easily!