CVE-2021-34593

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

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.

Remediation

Solution:

  • 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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.76% Top 30%
Vendor Advisory codesys.com
Affected: CODESYS CODESYS V2
Published at:
Updated at:

References

Link Tags
https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= vendor advisory
http://seclists.org/fulldisclosure/2021/Oct/64 third party advisory mailing list
http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html exploit vdb entry third party advisory
http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html exploit vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34593?
CVE-2021-34593 has been scored as a high severity vulnerability.
How to fix CVE-2021-34593?
To fix CVE-2021-34593: 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.
Is CVE-2021-34593 being actively exploited in the wild?
It is possible that CVE-2021-34593 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-34593?
CVE-2021-34593 affects CODESYS CODESYS V2.
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