CVE-2021-34595 - CVE House
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Status published High CVE-2021-34595

CODESYS V2 runtime: out-of-bounds read or write access may result in denial-of-service

Vulnerability Description

A crafted request with invalid offsets may cause an out-of-bounds read or write access in CODESYS V2 Runtime Toolkit 32 Bit full and PLCWinNT prior to versions V2.4.7.56, resulting in a denial-of-service condition or local memory overwrite.

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 Chen Jie and Gao Jian of NSFOCUS.

References

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Affected Vendor

Affected Software

CODESYS V2
Vulnerable Versions:
Runtime Toolkit 32 bit full, PLCWinNT

Timeline

Official Publish: October 26th, 2021
Last Modified: September 17th, 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:H/A:H

Weaknesses (CWE)

CWE-823

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.