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

7.5HIGH

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.

No summary for this CVE yet.

CVSS Vector Breakdown

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

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Weaknesses

CWE-755

Affected Products

and 5 more affected products View all →

Exploitability

2 exploit sources identified

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

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Official Patch Available

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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 →

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