CVE-2021-34595: CODESYS V2 runtime: out-of-bounds read or write access may result in denial-of-service

Published Oct 26, 2021
·
Updated

A crafted request with invalid offsets may cause an out-of-bounds read or write access in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56, resulting in a denial-of-service condition or local memory overwrite.

Affected Software

57 affected components
CODESYS PLCWinNT<2.4.7.56
CODESYS Runtime Toolkit<2.4.7.56
All of the following
WAGO 750-823 Firmware<fw10
WAGO 750-823
All of the following
WAGO 750-829 Firmware<fw17
WAGO 750-829
All of the following
WAGO 750-831 Firmware<fw17
WAGO 750-831
All of the following
WAGO 750-832 Firmware<fw10
WAGO 750-832
All of the following
WAGO 750-852 Firmware<fw17
WAGO 750-852
All of the following
WAGO 750-862 Firmware<fw10
WAGO 750-862
All of the following
WAGO 750-880 Firmware<fw17
WAGO 750-880
All of the following
WAGO 750-881 Firmware<fw17
WAGO 750-881
All of the following
WAGO 750-882 Firmware<fw17
WAGO 750-882
All of the following
WAGO 750-885 Firmware<fw17
WAGO 750-885
All of the following
WAGO 750-889 Firmware<fw17
WAGO 750-889
All of the following
WAGO 750-890 Firmware<fw10
WAGO 750-890
All of the following
WAGO 750-891 Firmware<fw10
WAGO 750-891
All of the following
WAGO 750-893 Firmware<fw10
WAGO 750-893
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
CODESYS CODESYS<1.1.9.22

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 the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2021-34595.

2

What is the severity rating of CVE-2021-34595?

The severity rating of CVE-2021-34595 is 8.1 (High).

3

What is the affected software for CVE-2021-34595?

The affected software for CVE-2021-34595 include CODESYS PLCWinNT (up to version 2.4.7.56) and Codesys Runtime Toolkit (up to version 2.4.7.56).

4

What can happen if a crafted request with invalid offsets is sent to the affected software?

A crafted request with invalid offsets may cause an out-of-bounds read or write access, resulting in a denial-of-service condition or local memory overwrite.

5

Is there a fix available for CVE-2021-34595?

Yes, updating CODESYS PLCWinNT and Codesys Runtime Toolkit to version 2.4.7.56 or later can fix the vulnerability.

Contact

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