CVE-2021-34585 - CVE House
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Status published High CVE-2021-34585

CODESYS V2 web server: crafted requests could trigger a pointer dereference with an invalid address (DoS)

Vulnerability Description

In the CODESYS V2 web server prior to V1.1.9.22 crafted web server requests can trigger a parser error. Since the parser result is not checked under all conditions, a pointer dereference with an invalid address can occur. This leads to a denial of service situation.

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 vulnerability was discovered by Tenable Research.

References

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Affected Vendor

Affected Software

CODESYS V2
Vulnerable Versions:
all web servers

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:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-252

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.