CVE-2021-37172

Name: CVE-2021-37172
Creator: NVD / NIST
Published: 2021-08-10T11:15:09.28+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.92%

Last modified Jun 17, 2026

CVE-2021-37172 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A vulnerability has been identified in SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (V4.5.0). EPSS estimates a 0.92% chance of exploitation in the next 30 days.

Description

A vulnerability has been identified in SIMATIC S7-1200 CPU family (incl. SIPLUS variants) (V4.5.0). Affected devices fail to authenticate against configured passwords when provisioned using TIA Portal V13. This could allow an attacker using TIA Portal V13 or later versions to bypass authentication and download arbitrary programs to the PLC. The vulnerability does not occur when TIA Portal V13 SP1 or any later version was used to provision the device.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

0.92%

55.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Siemens	Simatic S7-1200 Cpu Firmware	4.5.0
Siemens	Simatic Step 7 \(Tia Portal\)	<= 13.0

References

https://cert-portal.siemens.com/productcert/pdf/ssa-830194.pdfPatch, Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-830194.pdfPatch, Vendor Advisory

Timeline

Published: Aug 10, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-37172?

How severe is CVE-2021-37172?

CVE-2021-37172 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.92% probability of exploitation in the next 30 days.

How do I fix CVE-2021-37172?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-37172?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST