CVE-2021-42029

Name: CVE-2021-42029
Creator: NVD / NIST
Published: 2022-04-12T09:15:13.817+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 0.23%

Last modified Jun 17, 2026

CVE-2021-42029 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. A vulnerability has been identified in SIMATIC STEP 7 (TIA Portal) V15 (All versions), SIMATIC STEP 7 (TIA Portal) V16 (All versions < V16 Update 5), SIMATIC STEP 7 (TIA Portal) V17 (All versions < V17 Update 2). An attacker could achieve privilege escalation on the web server of certain devices due to improper access control vulnerability in the engineering system software. EPSS estimates a 0.23% chance of exploitation in the next 30 days.

Description

A vulnerability has been identified in SIMATIC STEP 7 (TIA Portal) V15 (All versions), SIMATIC STEP 7 (TIA Portal) V16 (All versions < V16 Update 5), SIMATIC STEP 7 (TIA Portal) V17 (All versions < V17 Update 2). An attacker could achieve privilege escalation on the web server of certain devices due to improper access control vulnerability in the engineering system software. The attacker needs to have direct access to the impacted web server.

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

0.23%

13.7th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-284

Affected Software

Vendor	Product	Versions
Siemens	Simatic Step 7	>= 15, < 16
Siemens	Simatic Step 7	16
Siemens	Simatic Step 7	17

References

https://cert-portal.siemens.com/productcert/pdf/ssa-350757.pdfPatch, Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-350757.pdfPatch, Vendor Advisory

Timeline

Published: Apr 12, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-42029?

How severe is CVE-2021-42029?

CVE-2021-42029 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.23% probability of exploitation in the next 30 days.

How do I fix CVE-2021-42029?

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-2021-42029?

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

Scan your code now

Source: NVD / NIST