CVE-2021-34581

WAGO: Denial of Service vulnerability inside the OpenSSL implementation

Description

Missing Release of Resource after Effective Lifetime vulnerability in OpenSSL implementation of WAGO 750-831/xxx-xxx, 750-880/xxx-xxx, 750-881, 750-889 in versions FW4 up to FW15 allows an unauthenticated attacker to cause DoS on the device.

Remediation

Solution:

  • Update the device to the latest FW version ( >FW15 ).

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 configuration phase.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.21% Top 25%
Third-Party Advisory vde.com
Affected: WAGO 750-831/xxx-xxx, 750-880/xxx-xxx, 750-881, 750-889
Published at:
Updated at:

References

Link Tags
https://cert.vde.com/en-us/advisories/vde-2021-038 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-34581?
CVE-2021-34581 has been scored as a high severity vulnerability.
How to fix CVE-2021-34581?
To fix CVE-2021-34581: Update the device to the latest FW version ( >FW15 ).
Is CVE-2021-34581 being actively exploited in the wild?
It is possible that CVE-2021-34581 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-2021-34581?
CVE-2021-34581 affects WAGO 750-831/xxx-xxx, 750-880/xxx-xxx, 750-881, 750-889.
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