CVE-2021-33541

Phoenix Contact: ILC1x Industrial controllers affected by Denial-of-Service vulnerability

Description

Phoenix Contact Classic Line Controllers ILC1x0 and ILC1x1 in all versions/variants are affected by a Denial-of-Service vulnerability. The communication protocols and device access do not feature authentication measures. Remote attackers can use specially crafted IP packets to cause a denial of service on the PLC's network communication module. A successful attack stops all network communication. To restore the network connectivity the device needs to be restarted. The automation task is not affected.

Remediation

Solution:

  • Temporary Fix / Mitigation 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

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.31% Top 25%
Third-Party Advisory vde.com
Affected: Phoenix Contact ILC1x
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2021-019 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-33541?
CVE-2021-33541 has been scored as a high severity vulnerability.
How to fix CVE-2021-33541?
To fix CVE-2021-33541: Temporary Fix / Mitigation 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-2021-33541 being actively exploited in the wild?
It is possible that CVE-2021-33541 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-33541?
CVE-2021-33541 affects Phoenix Contact ILC1x.
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