CVE-2021-34596
published 2021-10-26CVE-2021-34596: A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56…
PriorityP431medium6.5CVSS 3.1
AVNACLPRLUINSUCNINAH
EPSS
0.83%
53.4th percentile
A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56, resulting in a denial-of-service condition.
Affected
32 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| codesys | codesys | < 1.1.9.22 | 1.1.9.22 |
| codesys | codesys_v2 | >= PLCWinNT < V2.4.7.56 | V2.4.7.56 |
| codesys | codesys_v2 | >= Runtime Toolkit 32 bit full < V2.4.7.56 | V2.4.7.56 |
| codesys | plcwinnt | < 2.4.7.56 | 2.4.7.56 |
| codesys | runtime_toolkit | < 2.4.7.56 | 2.4.7.56 |
| wago | 750-8202_firmware | < fw20 | fw20 |
| wago | 750-8203_firmware | < fw20 | fw20 |
| wago | 750-8204_firmware | < fw20 | fw20 |
| wago | 750-8206_firmware | < fw20 | fw20 |
| wago | 750-8207_firmware | < fw20 | fw20 |
| wago | 750-8208_firmware | < fw20 | fw20 |
| wago | 750-8210_firmware | < fw20 | fw20 |
| wago | 750-8211_firmware | < fw20 | fw20 |
| wago | 750-8212_firmware | < fw20 | fw20 |
| wago | 750-8213_firmware | < fw20 | fw20 |
| wago | 750-8214_firmware | < fw20 | fw20 |
| wago | 750-8216_firmware | < fw20 | fw20 |
| wago | 750-8217_firmware | < fw20 | fw20 |
| wago | 750-823_firmware | < fw10 | fw10 |
| wago | 750-829_firmware | < fw17 | fw17 |
| wago | 750-831_firmware | < fw17 | fw17 |
| wago | 750-832_firmware | < fw10 | fw10 |
| wago | 750-852_firmware | < fw17 | fw17 |
| wago | 750-862_firmware | < fw10 | fw10 |
| wago | 750-880_firmware | < fw17 | fw17 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvdv2.04.0MEDIUMAV:N/AC:L/Au:S/C:N/I:N/A:P
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CISA ICS
CODESYS in Festo Automation Suite
cisa_ics·2026-03-17
CODESYS in Festo Automation Suite
ICS Advisory
##
CODESYS in Festo Automation Suite
Release DateMarch 17, 2026
Alert CodeICSA-26-076-01
Related topics:
Industrial Control System Vulnerabilities, Industrial Control Systems
View CSAF
## Summary
3. TECHNICAL DETAILS
The following versions of CODESYS in Festo Automation Suite are affected:
- FESTO Software Festo Automation Suite (versions prior to 2.8.0.138) installed with CODESYS Software CODESYS Development System (3.0) vers:all/*
- FESTO Software Festo Automation Suite (versions prior to 2.8.0.138) installed with CODESYS Software CODESYS Development System (3.5.16.10) vers:all/*
- FESTO Software Festo Automation Suite (2.8.0.137) installed with CODESYS Software CODESYS Development System (3.0) vers:all/*
- FESTO Software Festo Automation
GHSA
GHSA-93x3-2r5r-4375: A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2
ghsa_unreviewed·2022-05-24
CVE-2021-34596 [MEDIUM] CWE-824 GHSA-93x3-2r5r-4375: A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2
A crafted request may cause a read access to an uninitialized pointer in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56, resulting in a denial-of-service condition.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-10-26
Published