Codesys
CVE-2021-30190
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A07:2025 - Authentication Failures
ASVS 5.0
V6 - Authentication Authentication required for critical functions
MITRE ATT&CK
1 technique across 1 tactic: Initial Access The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | A remote attacker could access critical functionality without authentication by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
CODESYS V2 Web-Server before 1.1.9.20 has Improper Access Control. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Require authentication for all sensitive operations, implement defense in depth.
Affects your stack
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Technical ContextAI · show details
This vulnerability is classified as Missing Authentication for Critical Function (CWE-306), which allows attackers to access critical functionality without authentication. CODESYS V2 Web-Server before 1.1.9.20 has Improper Access Control. Affected products include: Wago 750-893 Firmware, Wago 750-891 Firmware, Wago 750-890 Firmware, Wago 750-889 Firmware, Wago 750-885 Firmware. Version information: before 1.1.9.20.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
CODESYS V2 Web-Server before 1.1.9.20 has Improper Access Control.
Threat Intelligence Overview
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
CODESYS V3 web server before 3.5.15.40, as used in CODESYS Control runtime systems, has a buffer overflow. Rated critica
CODESYS 3 web server before 3.5.15.20, as distributed with CODESYS Control runtime systems, has a Buffer Overflow. Rated
Crafted web server requests can be utilised to read partial stack or heap memory or may trigger a denial-of- service con
An exploitable code execution vulnerability exists in the PLC_Task functionality of 3S-Smart Software Solutions GmbH COD
An unsafe deserialization vulnerability exists in the Engine.plugin ProfileInformation ProfileData functionality of CODE
An unsafe deserialization vulnerability exists in the ObjectManager.plugin Project.get_MissingTypes() functionality of C
An unsafe deserialization vulnerability exists in the ObjectManager.plugin ObjectStream.ProfileByteArray functionality o
A unsafe deserialization vulnerability exists in the ObjectManager.plugin ProfileInformation.ProfileData functionality o
A unsafe deserialization vulnerability exists in the ComponentModel ComponentManager.StartupCultureSettings functionalit
The Package Manager of CODESYS Development System 3 before 3.5.17.0 does not check the validity of packages before insta
In CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56 unauthenticated crafted invalid reque
In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests may cause a Null pointer dereference in the
NVD
CVE.org
EPSS
GitHub PoC
Exploit-DB