CVE-2021-21002

Denial of Service in Phoenix Contact FL COMSERVER UNI products

Description

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

Remediation

Solution:

  • Upgrade to the latest firmware, fixed firmware includes versions >= 2.41.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.33%
Third-Party Advisory vde.com
Affected: Phoenix Contact FL COMSERVER
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2021-022 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21002?
CVE-2021-21002 has been scored as a high severity vulnerability.
How to fix CVE-2021-21002?
To fix CVE-2021-21002: Upgrade to the latest firmware, fixed firmware includes versions >= 2.41.
Is CVE-2021-21002 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21002 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21002?
CVE-2021-21002 affects Phoenix Contact FL COMSERVER.
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