CVE-2021-33716

Name: CVE-2021-33716
Creator: NVD / NIST
Published: 2021-09-14T11:15:24.347+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 0.24%

Last modified Jun 17, 2026

CVE-2021-33716 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. A vulnerability has been identified in SIMATIC CP 1543-1 (incl. SIPLUS variants) (All versions < V3.0), SIMATIC CP 1545-1 (All versions < V1.1). EPSS estimates a 0.24% chance of exploitation in the next 30 days.

Description

A vulnerability has been identified in SIMATIC CP 1543-1 (incl. SIPLUS variants) (All versions < V3.0), SIMATIC CP 1545-1 (All versions < V1.1). An attacker with access to the subnet of the affected device could retrieve sensitive information stored in cleartext.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

0.24%

15.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Siemens	Simatic Cp 1543-1 Firmware	< 3.0
Siemens	Simatic Cp 1545-1 Firmware	< 1.1

References

https://cert-portal.siemens.com/productcert/pdf/ssa-535997.pdfPatch, Vendor Advisory
https://cert-portal.siemens.com/productcert/pdf/ssa-535997.pdfPatch, Vendor Advisory

Timeline

Published: Sep 14, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-33716?

How severe is CVE-2021-33716?

CVE-2021-33716 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.

How do I fix CVE-2021-33716?

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-2021-33716?

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

Scan your code now

Source: NVD / NIST