CVE-2021-21000

WAGO: PFC200 Denial of Service due to the number of connections to the runtime

Description

On WAGO PFC200 devices in different firmware versions with special crafted packets an attacker with network access to the device could cause a denial of service for the login service of the runtime.

Remediation

Solution:

  • WAGO recommends all effected users with CODESYS 2.3 Runtime PLCs to update to the firmware versions listed at https://cert.vde.com/en-us/advisories/vde-2021-014 in the solution paragraph.

Workaround:

  • Use general security best practices to protect systems from local and network attacks. Do not allow direct access to the device from untrusted networks. Update to the latest firmware according to the table in chapter solutions.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.13%
Third-Party Advisory vde.com
Affected: WAGO Series PFC200 Controller
Affected: WAGO Series Ethernet Controller
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2021-014 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21000?
CVE-2021-21000 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21000?
To fix CVE-2021-21000: WAGO recommends all effected users with CODESYS 2.3 Runtime PLCs to update to the firmware versions listed at https://cert.vde.com/en-us/advisories/vde-2021-014 in the solution paragraph.
Is CVE-2021-21000 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21000 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-2021-21000?
CVE-2021-21000 affects WAGO Series PFC200 Controller, WAGO Series Ethernet Controller.
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