CVE-2021-21002 - CVE House
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Status published High CVE-2021-21002

Denial of Service in Phoenix Contact FL COMSERVER UNI products

Vulnerability Description

In Phoenix Contact FL COMSERVER UNI in versions < 2.40 a invalid Modbus exception response can lead to a temporary denial of service.

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 found by Petri Tuomio and reported to PHOENIX CONTACT by Waertsilae PSIRT. PHOENIX CONTACT thanks CERT@VDE for the coordination and support with this publication.

References

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Affected Vendor

Phoenix Contact

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Affected Software

FL COMSERVER
Vulnerable Versions:
UNI 232/422/485 (2313452), UNI 232/422/485-T (2904817)

Timeline

Official Publish: June 25th, 2021
Last Modified: September 17th, 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-772

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.