CVE-2021-34593: CODESYS V2 runtime: unauthenticated invalid requests may result in denial-of-service

Published Oct 26, 2021
·
Updated

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.

Affected Software

28 affected components
CODESYS PLCWinNT<2.4.7.56
CODESYS Runtime Toolkit<2.4.7.56
All of the following
WAGO 750-8202 Firmware<fw20
WAGO 750-8202
All of the following
WAGO 750-8203 Firmware<fw20
WAGO 750-8203
All of the following
WAGO 750-8204 Firmware<fw20
WAGO 750-8204
All of the following
WAGO 750-8206 Firmware<fw20
WAGO 750-8206
All of the following
WAGO 750-8207 Firmware<fw20
WAGO 750-8207
All of the following
WAGO 750-8208 Firmware<fw20
WAGO 750-8208
All of the following
WAGO 750-8210 Firmware<fw20
WAGO 750-8210
All of the following
WAGO 750-8211 Firmware<fw20
WAGO 750-8211
All of the following
WAGO 750-8212 Firmware<fw20
WAGO 750-8212
All of the following
WAGO 750-8213 Firmware<fw20
WAGO 750-8213
All of the following
WAGO 750-8214 Firmware<fw20
WAGO 750-8214
All of the following
WAGO 750-8216 Firmware<fw20
WAGO 750-8216
All of the following
WAGO 750-8217 Firmware<fw20
WAGO 750-8217

Remediation

Information

CODESYS GmbH has released the following product versions to solve the noted vulnerability issue for the affected CODESYS products: * CODESYS Runtime Toolkit 32 bit full version V2.4.7.56 * CODESYS PLCWinNT version V2.4.7.56. This will also be part of the CODESYS Development System setup version V2.3.9.68.

Event History

Oct 26, 2021
CVE Published
via MITRE·09:55 AM
Data Sourced
via MITRE·09:55 AM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·10:15 AM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2021-34593?

CVE-2021-34593 is a vulnerability found in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56, which can result in denial-of-service conditions.

2

What is the severity of CVE-2021-34593?

CVE-2021-34593 has a severity rating of 7.5 (high).

3

How does CVE-2021-34593 impact PLC programs?

CVE-2021-34593 can stop running PLC programs or cause memory leaks.

4

How can CVE-2021-34593 affect communication clients?

CVE-2021-34593 can block further communication clients from accessing the affected system.

5

Is there a fix available for CVE-2021-34593?

Yes, updating to versions V2.4.7.56 or above of CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT can fix the vulnerability.

Contact

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