CVE-2021-34578

WAGO: Authentication Vulnerability in Web-Based Management

Description

This vulnerability allows an attacker who has access to the WBM to read and write settings-parameters of the device by sending specifically constructed requests without authentication on multiple WAGO PLCs in firmware versions up to FW07.

Remediation

Solution:

  • Update the device to the latest FW version.

Workaround:

  • Restrict network access to the device. Do not directly connect the device to the internet. Disable unused TCP/UDP ports. Disable web-based management ports 80/443 after the configuration phase

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.32%
Third-Party Advisory vde.com
Affected: WAGO PLC
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2020-044 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34578?
CVE-2021-34578 has been scored as a critical severity vulnerability.
How to fix CVE-2021-34578?
To fix CVE-2021-34578: Update the device to the latest FW version.
Is CVE-2021-34578 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-34578 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-2021-34578?
CVE-2021-34578 affects WAGO PLC.
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