CVE-2021-21004

Cross-site Scripting Vulnerability in Phoenix Contact FL SWITCH SMCS series products

Description

In Phoenix Contact FL SWITCH SMCS series products in multiple versions an attacker may insert malicious code via LLDP frames into the web-based management which could then be executed by the client.

Remediation

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 the Phoenix Contact application note: Measures to protect network-capable devices with Ethernet connection https://dam-mdc.phoenixcontact.com/asset/156443151564/0a870ae433c19148b80bd760f3a1c1f2/107913_en_03.pdf

Category

7.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Third-Party Advisory vde.com
Affected: Phoenix Contact FL SWITCH
Affected: Phoenix Contact FL NAT
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2021-023 third party advisory not applicable

Frequently Asked Questions

What is the severity of CVE-2021-21004?
CVE-2021-21004 has been scored as a high severity vulnerability.
How to fix CVE-2021-21004?
As a workaround for remediating CVE-2021-21004: 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 the Phoenix Contact application note: Measures to protect network-capable devices with Ethernet connection https://dam-mdc.phoenixcontact.com/asset/156443151564/0a870ae433c19148b80bd760f3a1c1f2/107913_en_03.pdf
Is CVE-2021-21004 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21004 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-2021-21004?
CVE-2021-21004 affects Phoenix Contact FL SWITCH, Phoenix Contact FL NAT.
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