CVE-2021-34570

Phoenix Contact: DoS for PLCnext Control devices in versions prior to 2021.0.5 LTS

Description

Multiple Phoenix Contact PLCnext control devices in versions prior to 2021.0.5 LTS are prone to a DoS attack through special crafted JSON requests.

Remediation

Solution:

  • Phoenix Contact recommends affected users to upgrade to the current Firmware 2021.0.5 LTS or higher which fixes this vulnerability.

Workaround:

  • Phoenix Contact recommends operating network-capable devices in closed networks or protected with a suitable firewall. For detailed information on our recommendations for measures to protect network-capable devices, please refer to our application note: Measures to protect network-capable devices with Ethernet connection

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.45%
Third-Party Advisory vde.com
Affected: Phoenix Contact AXC F
Affected: Phoenix Contact RFC
Affected: Phoenix Contact PLCnext
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en/advisories/VDE-2021-029/ third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-34570?
CVE-2021-34570 has been scored as a high severity vulnerability.
How to fix CVE-2021-34570?
To fix CVE-2021-34570: Phoenix Contact recommends affected users to upgrade to the current Firmware 2021.0.5 LTS or higher which fixes this vulnerability.
Is CVE-2021-34570 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34570 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-2021-34570?
CVE-2021-34570 affects Phoenix Contact AXC F, Phoenix Contact RFC, Phoenix Contact PLCnext.
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