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TI-2021-15248 Aliases CVE-2021-37186GHSA-5g5j-x767-23r3

A vulnerability has been identified in LOGO! CMR2020 (All versions < V2.2), LOGO! CMR2040…

Priority LOW 24CWE-330Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.00356 29th percentileScored 2026-11-07
Fix Fixed LOGO! CMR2020 (Siemens): V2.2LOGO! CMR2040 (Siemens): V2.2+4 more products

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
SiemensLOGO! CMR2020before V2.2V2.2Patch availableCNA
SiemensLOGO! CMR2040before V2.2V2.2Patch availableCNA
SiemensSIMATIC RTU3010Cbefore V4.0.9V4.0.9Patch availableCNA
SiemensSIMATIC RTU3030Cbefore V4.0.9V4.0.9Patch availableCNA
SiemensSIMATIC RTU3031Cbefore V4.0.9V4.0.9Patch availableCNA
SiemensSIMATIC RTU3041Cbefore V4.0.9V4.0.9Patch availableCNA
  • LOGO! CMR2020 VendorSiemens Affected before V2.2 Fixed in V2.2 Patch available CNA
  • LOGO! CMR2040 VendorSiemens Affected before V2.2 Fixed in V2.2 Patch available CNA
  • SIMATIC RTU3010C VendorSiemens Affected before V4.0.9 Fixed in V4.0.9 Patch available CNA
  • SIMATIC RTU3030C VendorSiemens Affected before V4.0.9 Fixed in V4.0.9 Patch available CNA
  • SIMATIC RTU3031C VendorSiemens Affected before V4.0.9 Fixed in V4.0.9 Patch available CNA
  • SIMATIC RTU3041C VendorSiemens Affected before V4.0.9 Fixed in V4.0.9 Patch available CNA

CPE configurations NVD · 12

CPEVersionsRoleVendor
cpe:2.3:o:siemens:logo\!_cmr2020_firmware:*:*:*:*:*:*:*:*before 2.2VulnerableSiemens
cpe:2.3:h:siemens:logo\!_cmr2020:-:*:*:*:*:*:*:*not specified by NVDRunning onSiemens
cpe:2.3:o:siemens:logo\!_cmr2040_firmware:*:*:*:*:*:*:*:*before 2.2VulnerableSiemens
cpe:2.3:h:siemens:logo\!_cmr2040:-:*:*:*:*:*:*:*not specified by NVDRunning onSiemens
cpe:2.3:o:siemens:simatic_rtu3010c_firmware:*:*:*:*:*:*:*:*before 4.0.9VulnerableSiemens
cpe:2.3:h:siemens:simatic_rtu3010c:*:*:*:*:*:*:*:*all versionsRunning onSiemens
cpe:2.3:o:siemens:simatic_rtu3030c_firmware:*:*:*:*:*:*:*:*before 4.0.9VulnerableSiemens
cpe:2.3:h:siemens:simatic_rtu3030c:*:*:*:*:*:*:*:*all versionsRunning onSiemens
cpe:2.3:o:siemens:simatic_rtu3031c_firmware:*:*:*:*:*:*:*:*before 4.0.9VulnerableSiemens
cpe:2.3:h:siemens:simatic_rtu3031c:*:*:*:*:*:*:*:*all versionsRunning onSiemens
  • cpe:2.3:o:siemens:logo\!_cmr2020_firmware:*:*:*:*:*:*:*:* Versions before 2.2 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:logo\!_cmr2020:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
  • cpe:2.3:o:siemens:logo\!_cmr2040_firmware:*:*:*:*:*:*:*:* Versions before 2.2 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:logo\!_cmr2040:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Siemens
  • cpe:2.3:o:siemens:simatic_rtu3010c_firmware:*:*:*:*:*:*:*:* Versions before 4.0.9 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simatic_rtu3010c:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens
  • cpe:2.3:o:siemens:simatic_rtu3030c_firmware:*:*:*:*:*:*:*:* Versions before 4.0.9 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simatic_rtu3030c:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens
  • cpe:2.3:o:siemens:simatic_rtu3031c_firmware:*:*:*:*:*:*:*:* Versions before 4.0.9 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simatic_rtu3031c:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens
Show 2 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:siemens:simatic_rtu3041c_firmware:*:*:*:*:*:*:*:*before 4.0.9VulnerableSiemens
cpe:2.3:h:siemens:simatic_rtu3041c:*:*:*:*:*:*:*:*all versionsRunning onSiemens
  • cpe:2.3:o:siemens:simatic_rtu3041c_firmware:*:*:*:*:*:*:*:* Versions before 4.0.9 Vulnerable ·Siemens
  • cpe:2.3:h:siemens:simatic_rtu3041c:*:*:*:*:*:*:*:* Versions all versions Running on ·Siemens

Remediation

  • Fix · CNA LOGO! CMR2020 (Siemens) Fixed in V2.2
  • Fix · CNA LOGO! CMR2040 (Siemens) Fixed in V2.2
  • Fix · CNA SIMATIC RTU3010C (Siemens) Fixed in V4.0.9
  • Fix · CNA SIMATIC RTU3030C (Siemens) Fixed in V4.0.9
  • Fix · CNA SIMATIC RTU3031C (Siemens) Fixed in V4.0.9
  • Fix · CNA SIMATIC RTU3041C (Siemens) Fixed in V4.0.9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-37186
  2. 2026-10-03 Alias added: GHSA-5g5j-x767-23r3

References

Patch 1

  • TI-2021-05785 Improper input validation in https://github.com/curl/curl CVSS 3.1LOW 3.7
  • TI-2020-18723 An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before… CVSS 3.1HIGH 7.5
  • TI-2020-18726 An issue was discovered in Mbed TLS before 2.25.0 (and before 2.16.9 LTS and before… CVSS 3.1HIGH 7.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences