Vulnerability · Published Sep 14, 2021 · Assigned by siemens

CVE-2021-37186

Medium 5.4

In plain English

A medium-severity weak randomness in LOGO! CMR2020 from Siemens. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 30% of all known vulnerabilities).

Severity (CVSS NVD)5.4Medium

Exploit odds (30 days)0.4%top 70.5% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
Siemens	LOGO! CMR2020	All versions < V2.2
Siemens	LOGO! CMR2040	All versions < V2.2
Siemens	SIMATIC RTU3010C	All versions < V4.0.9
Siemens	SIMATIC RTU3030C	All versions < V4.0.9
Siemens	SIMATIC RTU3031C	All versions < V4.0.9
Siemens	SIMATIC RTU3041C	All versions < V4.0.9

Weakness: CWE-330

References

https://cert-portal.siemens.com/productcert/pdf/ssa-316383.pdf x_refsource_MISC