CVE-2021-37186

Description

A vulnerability has been identified in LOGO! CMR2020 (All versions < V2.2), LOGO! CMR2040 (All versions < V2.2), SIMATIC RTU3010C (All versions < V4.0.9), SIMATIC RTU3030C (All versions < V4.0.9), SIMATIC RTU3031C (All versions < V4.0.9), SIMATIC RTU3041C (All versions < V4.0.9). The underlying TCP/IP stack does not properly calculate the random numbers used as ISN (Initial Sequence Numbers). An adjacent attacker with network access to the LAN interface could interfere with traffic, spoof the connection and gain access to sensitive information.

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.17%
Vendor Advisory siemens.com
Affected: Siemens LOGO! CMR2020
Affected: Siemens LOGO! CMR2040
Affected: Siemens SIMATIC RTU3010C
Affected: Siemens SIMATIC RTU3030C
Affected: Siemens SIMATIC RTU3031C
Affected: Siemens SIMATIC RTU3041C
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-37186?
CVE-2021-37186 has been scored as a medium severity vulnerability.
How to fix CVE-2021-37186?
To fix CVE-2021-37186, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37186 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-37186 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-2021-37186?
CVE-2021-37186 affects Siemens LOGO! CMR2020, Siemens LOGO! CMR2040, Siemens SIMATIC RTU3010C, Siemens SIMATIC RTU3030C, Siemens SIMATIC RTU3031C, Siemens SIMATIC RTU3041C.
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