CVE-2021-34593
CODESYS Denial-of-Service Vulnerability
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.
INFO
Published Date :
Oct. 26, 2021, 10:15 a.m.
Last Modified :
Aug. 15, 2025, 8:25 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2021-34593
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 2.0 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] |
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-34593.
| URL | Resource |
|---|---|
| http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html | Exploit Third Party Advisory VDB Entry |
| http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html | Exploit Third Party Advisory VDB Entry |
| http://seclists.org/fulldisclosure/2021/Oct/64 | Mailing List Third Party Advisory |
| https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= | Vendor Advisory |
| http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html | Exploit Third Party Advisory VDB Entry |
| http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html | Exploit Third Party Advisory VDB Entry |
| http://seclists.org/fulldisclosure/2021/Oct/64 | Mailing List Third Party Advisory |
| https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-34593 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-34593
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-34593 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-34593 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Modified Analysis by [email protected]
Aug. 15, 2025
Action Type Old Value New Value Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8202_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8202:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8203_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8203:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8204_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8204:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8206_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8206:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8207_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8207:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8208_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8208:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8210_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8210:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8211_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8211:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8212_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8212:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8213_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8213:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8214_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8214:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8216_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8216:-:*:*:*:*:*:*:* Added CPE Configuration AND OR *cpe:2.3:o:wago:750-8217_firmware:*:*:*:*:*:*:*:* versions up to (excluding) fw20 OR cpe:2.3:h:wago:750-8217:-:*:*:*:*:*:*:* -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html Added Reference http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html Added Reference http://seclists.org/fulldisclosure/2021/Oct/64 Added Reference https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= -
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Modified Analysis by [email protected]
Apr. 12, 2022
Action Type Old Value New Value Changed Reference Type http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html Third Party Advisory, VDB Entry http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html Exploit, Third Party Advisory, VDB Entry Changed Reference Type http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html No Types Assigned http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html Exploit, Third Party Advisory, VDB Entry -
CVE Modified by [email protected]
Feb. 04, 2022
Action Type Old Value New Value Added Reference http://packetstormsecurity.com/files/165874/WAGO-750-8xxx-PLC-Denial-Of-Service-User-Enumeration.html [No Types Assigned] -
Modified Analysis by [email protected]
Nov. 23, 2021
Action Type Old Value New Value Changed Reference Type http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html No Types Assigned http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html Third Party Advisory, VDB Entry Changed Reference Type http://seclists.org/fulldisclosure/2021/Oct/64 No Types Assigned http://seclists.org/fulldisclosure/2021/Oct/64 Mailing List, Third Party Advisory -
CVE Modified by [email protected]
Nov. 17, 2021
Action Type Old Value New Value Added Reference http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html [No Types Assigned] Added Reference http://seclists.org/fulldisclosure/2021/Oct/64 [No Types Assigned] -
CVE Modified by [email protected]
Nov. 10, 2021
Action Type Old Value New Value Removed Reference http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html [Third Party Advisory, VDB Entry] Removed Reference http://seclists.org/fulldisclosure/2021/Oct/64 [Mailing List, Third Party Advisory] -
Modified Analysis by [email protected]
Nov. 04, 2021
Action Type Old Value New Value Changed Reference Type http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html No Types Assigned http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html Third Party Advisory, VDB Entry Changed Reference Type http://seclists.org/fulldisclosure/2021/Oct/64 No Types Assigned http://seclists.org/fulldisclosure/2021/Oct/64 Mailing List, Third Party Advisory Changed CPE Configuration OR *cpe:2.3:a:codesys:plcwinnt:*:*:*:*:*:*:*:* versions up to (excluding) 2.4.7.54 *cpe:2.3:a:codesys:runtime_toolkit:*:*:*:*:*:*:*:* versions up to (excluding) 3.5.16.0 OR *cpe:2.3:a:codesys:plcwinnt:*:*:*:*:*:*:*:* versions up to (excluding) 2.4.7.56 *cpe:2.3:a:codesys:runtime_toolkit:*:*:*:*:*:*:x86:* versions up to (excluding) 2.4.7.56 -
CVE Modified by [email protected]
Nov. 01, 2021
Action Type Old Value New Value Added Reference http://packetstormsecurity.com/files/164716/CODESYS-2.4.7.0-Denial-Of-Service.html [No Types Assigned] -
CVE Modified by [email protected]
Oct. 29, 2021
Action Type Old Value New Value Added Reference http://seclists.org/fulldisclosure/2021/Oct/64 [No Types Assigned] -
Initial Analysis by [email protected]
Oct. 28, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= No Types Assigned https://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16877&token=8faab0fc1e069f4edfca5d5aba8146139f67a175&download= Vendor Advisory Added CPE Configuration OR *cpe:2.3:a:codesys:plcwinnt:*:*:*:*:*:*:*:* versions up to (excluding) 2.4.7.54 *cpe:2.3:a:codesys:runtime_toolkit:*:*:*:*:*:*:*:* versions up to (excluding) 3.5.16.0
Vulnerability Scoring Details
Base CVSS Score: 7.5
Base CVSS Score: 5
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
1.60 }} 0.68%
score
0.80881
percentile