ICSA-20-105-07: Siemens SCALANCE and SIMATIC (Update H)

CISA's summary

Summary: The products listed below contain a vulnerability that could allow remote attackers to affect the availability of the devices under certain conditions. The underlying TCP stack can be forced to make very computation expensive calls for every incoming packet which can lead to a Denial-of-Service. Siemens has released updates for several affected products and recommends to update to the latest versions. Siemens recommends specific countermeasures for products where updates are not, or not yet available.

Products, as the advisory lists them

DeSpy has not checked any unit, hardware revision or firmware.

Vulnerabilities in this advisory

• CVE-2019-19301 — CVE-2019-19301 · CWE-400

  The VxWorks-based Profinet TCP Stack can be forced to make very expensive calls for every incoming packet which can lead to a denial of service.

Acknowledgments, as the advisory lists them

• Siemens ProductCERT: reporting this vulnerability to CISA.

The advisory's legal notice

Siemens Security Advisories are subject to the terms and conditions contained in Siemens' underlying license terms or other applicable agreements previously agreed to with Siemens (hereinafter "License Terms"). To the extent applicable to information, software or documentation made available in or through a Siemens Security Advisory, the Terms of Use of Siemens' Global Website (https://www.siemens.com/terms_of_use, hereinafter "Terms of Use"), in particular Sections 8-10 of the Terms of Use, shall apply additionally. In case of conflicts, the License Terms shall prevail over the Terms of Use.

Sources

• The advisory at cisa.gov
• The CSAF document (JSON)

DeSpy's copy of this version is dated 2026-09-28.