CVE-2021-33720: High severity siemens siprotec 5 vulnerability

Published Sep 14, 2021
·
Updated

A vulnerability has been identified in SIPROTEC 5 relays with CPU variants CP050 (All versions < V8.80), SIPROTEC 5 relays with CPU variants CP100 (All versions < V8.80), SIPROTEC 5 relays with CPU variants CP300 (All versions < V8.80). Specially crafted packets sent to port 4443/tcp could cause a Denial-of-Service condition.

Affected Software

3 affected components
Siemens Siprotec 5 With Cpu Variant Cp050<8.80
Siemens Siprotec 5 With Cpu Variant Cp100<8.80
Siemens Siprotec 5 With Cpu Variant Cp300<8.80

Event History

Sep 14, 2021
CVE Published
via MITRE·10:47 AM
Data Sourced
via MITRE·10:47 AM
DescriptionWeakness
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Frequently Asked Questions

1

What is CVE-2021-33720?

CVE-2021-33720 is a vulnerability identified in SIPROTEC 5 relays with CPU variants CP050, CP100, and CP300. Specially crafted packets sent to port 4443/tcp could cause a DoS condition.

2

How does CVE-2021-33720 affect Siemens SIPROTEC 5 relays?

CVE-2021-33720 affects Siemens SIPROTEC 5 relays with CPU variants CP050, CP100, and CP300. It allows an attacker to cause a DoS condition by sending specially crafted packets to port 4443/tcp.

3

What is the severity of CVE-2021-33720?

The severity of CVE-2021-33720 is high, with a severity value of 7.5.

4

How do I fix CVE-2021-33720?

To fix CVE-2021-33720, Siemens recommends updating the affected SIPROTEC 5 relays to version 8.80 or higher.

5

Where can I find more information about CVE-2021-33720?

You can find more information about CVE-2021-33720 in the Siemens ProductCERT advisory at https://cert-portal.siemens.com/productcert/pdf/ssa-847986.pdf.

Contact

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