CVE-2021-37186: Medium severity Siemens Logo\! Cmr2020 Firmware vulnerability

Published Sep 14, 2021
·
Updated

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.

Affected Software

24 affected components
Siemens Logo\! Cmr2020 Firmware<2.2
Siemens Logo\! Cmr2020
Siemens Logo\! Cmr2040 Firmware<2.2
Siemens Logo\! Cmr2040
Siemens Simatic Rtu3010c Firmware<4.0.9
Siemens Simatic Rtu3010c
Siemens Simatic Rtu3030c Firmware<4.0.9
Siemens Simatic Rtu3030c
Siemens Simatic Rtu3031c Firmware<4.0.9
Siemens Simatic Rtu3031c
Siemens Simatic Rtu3041c Firmware<4.0.9
Siemens Simatic Rtu3041c
All of the following
Siemens Logo\! Cmr2020 Firmware<2.2
Siemens Logo\! Cmr2020
All of the following
Siemens Logo\! Cmr2040 Firmware<2.2
Siemens Logo\! Cmr2040
All of the following
Siemens Simatic Rtu3010c Firmware<4.0.9
Siemens Simatic Rtu3010c
All of the following
Siemens Simatic Rtu3030c Firmware<4.0.9
Siemens Simatic Rtu3030c
All of the following
Siemens Simatic Rtu3031c Firmware<4.0.9
Siemens Simatic Rtu3031c
All of the following
Siemens Simatic Rtu3041c Firmware<4.0.9
Siemens Simatic Rtu3041c

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade LOGO!/CMR2020 to a version that resolves this vulnerability.

    Fixed in V2.2
  2. Upgrade

    Upgrade LOGO!/CMR2040 to a version that resolves this vulnerability.

    Fixed in V2.2
  3. Upgrade

    Upgrade SIMATIC RTU3010C to a version that resolves this vulnerability.

    Fixed in V4.0.9
  4. Upgrade

    Upgrade SIMATIC RTU3030C to a version that resolves this vulnerability.

    Fixed in V4.0.9
  5. Upgrade

    Upgrade SIMATIC RTU3031C to a version that resolves this vulnerability.

    Fixed in V4.0.9
  6. Upgrade

    Upgrade SIMATIC RTU3041C to a version that resolves this vulnerability.

    Fixed in V4.0.9

Event History

Sep 14, 2021
CVE Published
via MITRE·10:47 AM
Data Sourced
via MITRE·10:47 AM
DescriptionWeakness
Data Sourced
via NVD·11:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2021-37186.

2

Which products are affected by this vulnerability?

This vulnerability affects 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), and SIMATIC RTU3041C (All versions < V4.0.9).

3

What is the severity rating of this vulnerability?

This vulnerability has a severity rating of 5.4 (Medium).

4

How can I fix this vulnerability?

To fix this vulnerability, update LOGO! CMR2020, LOGO! CMR2040, SIMATIC RTU3010C, SIMATIC RTU3030C, SIMATIC RTU3031C, and SIMATIC RTU3041C to versions equal or greater than V2.2 and V4.0.9 respectively.

5

Where can I find more information about this vulnerability?

You can find more information about this vulnerability at the following link: [Siemens Security Advisory SSA-316383](https://cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf)

Contact

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