CVE-2021-37204: Siemens SIMATIC Drive Controller CPU 1504d Tf Firmware

High severity, CVSS 7.5. EPSS: 2.2% chance of exploitation in the next 30 days.

A vulnerability has been identified in SIMATIC Drive Controller family (All versions < V2.9.2), SIMATIC Drive Controller family (All versions >= V2.9.2 < V2.9.4), SIMATIC ET 200SP Open Controller CPU 1515SP PC (incl. SIPLUS variants) (All versions), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions < V21.9), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants) (All versions >= V21.9 < V21.9.4), SIMATIC ET 200SP Open Controller CPU 1515SP PC2 Ready4Linux (All versions), SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (All versions < V4.5.0), 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), 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), SIMATIC S7-1500 Software Controller (All versions >= V21.9 < V21.9.4), SIMATIC S7-PLCSIM Advanced (All versions < V4.0), 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 packet over port 102/tcp. A restart of the affected device is needed to restore normal operations.

Affected products

Siemens SIMATIC Drive Controller CPU 1504d Tf Firmware: before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC Drive Controller CPU 1507d Tf Firmware: before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC Et 200sp Open Controller CPU 1515sp PC2 Firmware: any version
Siemens SIMATIC s7-1200 CPU 1211c Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1212c Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1212fc Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1214c Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1214fc Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1215c Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1215fc Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1200 CPU 1217c Firmware: from 4.5.0, before 4.5.2 (fixed in 4.5.2)
Siemens SIMATIC s7-1500 CPU 1510sp-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1510sp Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1511-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1511c-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1511f-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1511t-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1511tf-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1512c-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1512sp-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1512spf-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1513-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1513f-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1513r-1 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
Siemens SIMATIC s7-1500 CPU 1515-2 Firmware: from 2.9.2, before 2.9.4 (fixed in 2.9.4)
and 23 more

Published 2022-02-09. Last modified 2026-06-17.