CVE-2021-37186
Siemens · published 2021-09-14
Source record Collected from the National Vulnerability Database (NVD)
Description
Description by Siemens AG via the CVE Program.
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.
Status at the source
- NVD status: Modified
Affected products, as the source lists them
| Vendor | Product | Versions |
|---|---|---|
| Siemens | LOGO! CMR2020 | All versions < V2.2: affected |
| Siemens | LOGO! CMR2040 | All versions < V2.2: affected |
| Siemens | SIMATIC RTU3010C | All versions < V4.0.9: affected |
| Siemens | SIMATIC RTU3030C | All versions < V4.0.9: affected |
| Siemens | SIMATIC RTU3031C | All versions < V4.0.9: affected |
| Siemens | SIMATIC RTU3041C | All versions < V4.0.9: affected |
Products named in NVD's CPE match criteria (6)
cpe:2.3:o:siemens:logo\!_cmr2020_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:siemens:logo\!_cmr2040_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:siemens:simatic_rtu3010c_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:siemens:simatic_rtu3030c_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:siemens:simatic_rtu3031c_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:siemens:simatic_rtu3041c_firmware:*:*:*:*:*:*:*:*
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 3.1: 5.4 MEDIUM — as published by NIST (Primary)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N - CVSS 2.0: 4.8 MEDIUM — as published by NIST (Primary)
AV:A/AC:L/Au:N/C:P/I:P/A:N
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- https://cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf
- https://cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf
Source dates: published 2021-09-14, last changed 2026-06-17. DeSpy's copy of this version is dated 2026-09-28.
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