CVE-2021-33737

Description

A vulnerability has been identified in SIMATIC CP 343-1 (incl. SIPLUS variants) (All versions), SIMATIC CP 343-1 Advanced (incl. SIPLUS variants) (All versions), SIMATIC CP 343-1 ERPC (All versions), SIMATIC CP 343-1 Lean (incl. SIPLUS variants) (All versions), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 (All versions < V3.3), SIMATIC CP 443-1 Advanced (All versions < V3.3), SIPLUS NET CP 443-1 (All versions < V3.3), SIPLUS NET CP 443-1 Advanced (All versions < V3.3). Sending a specially crafted packet to port 102/tcp of an affected device could cause a denial of service condition. A restart is needed to restore normal operations.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.23%
Vendor Advisory siemens.com
Affected: Siemens SIMATIC CP 343-1 (incl. SIPLUS variants)
Affected: Siemens SIMATIC CP 343-1 Advanced (incl. SIPLUS variants)
Affected: Siemens SIMATIC CP 343-1 ERPC
Affected: Siemens SIMATIC CP 343-1 Lean (incl. SIPLUS variants)
Affected: Siemens SIMATIC CP 443-1
Affected: Siemens SIMATIC CP 443-1
Affected: Siemens SIMATIC CP 443-1 Advanced
Affected: Siemens SIPLUS NET CP 443-1
Affected: Siemens SIPLUS NET CP 443-1 Advanced
Published at:
Updated at:

References

Link Tags
https://cert-portal.siemens.com/productcert/pdf/ssa-549234.pdf patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-33737?
CVE-2021-33737 has been scored as a high severity vulnerability.
How to fix CVE-2021-33737?
To fix CVE-2021-33737, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-33737 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-33737 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-33737?
CVE-2021-33737 affects Siemens SIMATIC CP 343-1 (incl. SIPLUS variants), Siemens SIMATIC CP 343-1 Advanced (incl. SIPLUS variants), Siemens SIMATIC CP 343-1 ERPC, Siemens SIMATIC CP 343-1 Lean (incl. SIPLUS variants), Siemens SIMATIC CP 443-1, Siemens SIMATIC CP 443-1, Siemens SIMATIC CP 443-1 Advanced, Siemens SIPLUS NET CP 443-1, Siemens SIPLUS NET CP 443-1 Advanced.
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