CVE-2021-31894: Siemens SIMATIC Pcs 7 Firmware

High severity, CVSS 8.8. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability has been identified in SIMATIC PCS 7 V8.2 and earlier (All versions), SIMATIC PCS 7 V9.X (All versions < V9.1 SP2), SIMATIC PDM (All versions < V9.2 SP2), SIMATIC STEP 7 V5.X (All versions < V5.7), SINAMICS STARTER (containing STEP 7 OEM version) (All versions < V5.4 SP2 HF1). A directory containing metafiles relevant to devices' configurations has write permissions. An attacker could leverage this vulnerability by changing the content of certain metafiles and subsequently manipulate parameters or behavior of devices that would be later configured by the affected software.

Affected products

• Siemens SIMATIC Pcs 7 Firmware: up to and including 8.2; version 9.0 only
• Siemens SIMATIC Pdm Firmware: affected versions not specified
• Siemens SIMATIC Step 7 Firmware: from 5.0, before 5.7 (fixed in 5.7)
• Siemens Sinamics Starter Firmware: before 5.4 (fixed in 5.4); version 5.4 only

Published 2021-07-13. Last modified 2026-06-17.