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Simatic Drive Controller Cpu 1504d Tf FirmwareOperating system · Siemens

CVE-2021-37185

HIGH · 7.5 CVSS v3.1 Published 2022-02-09
Fix available
A fix is available. Upgrade to 2.9.4 / 4.0 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Simatic Drive Controller Cpu 1504d Tf FirmwareOperating system
Affected:< 2.9.4
Simatic Drive Controller Cpu 1507d Tf FirmwareOperating system
Affected:< 2.9.4
Simatic Et 200sp Open Controller Cpu 1515sp Pc2 FirmwareOperating system
Affected:all versions
Simatic S7 Plcsim Advanced FirmwareOperating system
Affected:< 4.0= 4.0
Tim 1531 Irc FirmwareOperating system
Affected:>= 2.2
Simatic S7 1500 Software ControllerApplication
Affected:all versions
Simatic S7 1200 Cpu 1211c FirmwareOperating system
Affected:>= 4.5.0, < 4.5.2
Simatic S7 1200 Cpu 1212c FirmwareOperating system
Affected:>= 4.5.0, < 4.5.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.9.4 / 4.0 / 4.5.2 or later
Fixed in 2.9.44.04.5.2
Vendor patch cert-portal.siemens.com →
Recommended fix High confidence

Firmware V2.9.4 (Drive Controller), V21.9.4 (ET200SP Open Controller, S7-1500 Software Controller), V4.5.2 (S7-1200), V2.9.4 (S7-1500), V4.0 SP1 (PLCSIM Advanced), V2.3.6 (TIM 1531 IRC)

  1. 1. Identify the specific Siemens SIMATIC device model and current firmware version from the affected product list.
  2. 2. For Simatic Drive Controller CPU 1504d TF and 1507d TF: Upgrade firmware to version 2.9.4 or later.
  3. 3. For Simatic ET 200SP Open Controller CPU 1515SP PC2: Upgrade firmware to version 21.9.4 or later.
  4. 4. For Simatic S7-1200 CPU 1211c and 1212c: Upgrade firmware to version 4.5.2 or later.
  5. 5. For Simatic S7-1500 CPU family (incl. ET200 CPUs): Upgrade firmware to version 2.9.4 or later.
  6. 6. For Simatic S7-1500 Software Controller: Upgrade to version 21.9.4 or later.
  7. 7. For Simatic S7-PLCSIM Advanced: Upgrade to version 4.0 SP1 or later.
  8. 8. For TIM 1531 IRC and SIPLUS TIM 1531 IRC: Upgrade firmware to version 2.3.6 or later.
Caveat firmware upgrades on industrial controllers may require PLC program revalidation; ensure backup of current project before upgrade

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

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