Vulnerability in Siemens Logo! Cmr2020
CVE-2021-37186
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.004 (26.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 27th percentile — 26.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Siemens Logo! Cmr2020 — versions All versions < V2.2
- Siemens Logo\! Cmr2020
- Siemens Logo\! Cmr2020 Firmware
- Siemens Logo! Cmr2040 — versions All versions < V2.2
- Siemens Logo\! Cmr2040
- Siemens Logo\! Cmr2040 Firmware
- Siemens Simatic Rtu3010c — versions All versions < V4.0.9
- Siemens Simatic Rtu3010c
- Siemens Simatic Rtu3010c Firmware
- Siemens Simatic Rtu3030c — versions All versions < V4.0.9
Weakness classification (CWE)
References
- cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf (Patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2021-37186?
- CVE-2021-37186 is a medium-severity vulnerability in Siemens Logo! Cmr2020, classified under Use of Insufficiently Random Values. CVSS score: 5.4/10. Published 2021-09-14.
- How severe is CVE-2021-37186?
- Medium severity. CVSS v3 base score is 5.4 out of 10.