CVE-2021-37185

Description

A vulnerability has been identified in SIMATIC Drive Controller family (All versions >= V2.9.2 < V2.9.4), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions >= V21.9 < V21.9.4), SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (All versions >= V4.5.0 < V4.5.2), SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants) (All versions >= V2.9.2 < V2.9.4), SIMATIC S7-1500 Software Controller (All versions >= V21.9 < V21.9.4), SIMATIC S7-PLCSIM Advanced (All versions >= V4.0 < V4.0 SP1), SIPLUS TIM 1531 IRC (All versions < V2.3.6), TIM 1531 IRC (All versions < V2.3.6). An unauthenticated attacker could cause a denial-of-service condition in a PLC when sending specially prepared packets over port 102/tcp. A restart of the affected device is needed to restore normal operations.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.43% Top 25%
Vendor Advisory siemens.com
Affected: Siemens SIMATIC Drive Controller family
Affected: Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)
Affected: Siemens SIMATIC S7-1200 CPU family (incl. SIPLUS variants)
Affected: Siemens SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants)
Affected: Siemens SIMATIC S7-1500 Software Controller
Affected: Siemens SIMATIC S7-PLCSIM Advanced
Affected: Siemens SIPLUS TIM 1531 IRC
Affected: Siemens TIM 1531 IRC
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-838121.pdf patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-37185?
CVE-2021-37185 has been scored as a high severity vulnerability.
How to fix CVE-2021-37185?
To fix CVE-2021-37185, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-37185 being actively exploited in the wild?
It is possible that CVE-2021-37185 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37185?
CVE-2021-37185 affects Siemens SIMATIC Drive Controller family, Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants), Siemens SIMATIC S7-1200 CPU family (incl. SIPLUS variants), Siemens SIMATIC S7-1500 CPU family (incl. related ET200 CPUs and SIPLUS variants), Siemens SIMATIC S7-1500 Software Controller, Siemens SIMATIC S7-PLCSIM Advanced, Siemens SIPLUS TIM 1531 IRC, Siemens TIM 1531 IRC.
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