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Status published
Medium
CVE-2021-34596
CODESYS V2 runtime: Access of Uninitialized Pointer may result in denial-of-service
Vulnerability Description
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.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- This issue was reported by Gao Jian of NSFOCUS.
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Affected Vendor
CODESYS
View all reports →Affected Software
CODESYS V2
Vulnerable Versions:
Runtime Toolkit 32 bit full, PLCWinNT
Timeline
Official Publish:
October 26th, 2021
Last Modified:
September 16th, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H