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CVE-2021-34593

CODESYS V2 runtime: unauthenticated invalid requests may result in denial-of-service

Published: Oct 26, 2021Updated: Aug 15, 2025 Sources: CVE List NVD csafCWE-755
NVD MITRE
7.5CVSSHIGH
EPSS Score
2.6%
Top 16.4%
CISA KEV
Not in KEV
Exploits
2 Known
Remediation
Patch Available

Description

In CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56 unauthenticated crafted invalid requests may result in several denial-of-service conditions. Running PLC programs may be stopped, memory may be leaked, or further communication clients may be blocked from accessing the PLC.

CVSS Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:NI:NA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-755

Affected Products

CODESYS V2CODESYSICS / OT / IoT
750-8202 firmwarewagoICS / OT / IoT
750-8203 firmwarewagoICS / OT / IoT
750-8204 firmwarewagoICS / OT / IoT
750-8206 firmwarewagoICS / OT / IoT
codesysoss-projectDEICS / OT / IoTaka codesys gmbh
wagocommercialDEICS / OT / IoT
and 11 more affected products View all →

Exploitability

2 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

References

https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download=
customers.codesys.com
http://seclists.org/fulldisclosure/2021/Oct/64
seclists.org
http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html
packetstormsecurity.com
and 229 more references View all →

Timeline

Published
Oct 26, 2021
Last Updated
Aug 15, 2025

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