Skip to content
OpenAdvisories
High SSA-674753 1 CVE

SSA-674753: Denial-of-Service Vulnerability in ET 200 Devices

Published Jan 13, 2026 · Updated Jun 9, 2026 · Revision 3

Vendor: Siemens Product: SIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0) Product: SIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0) Product: SIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0) Product: SIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants) Product: SIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0) Product: SIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0) Product: SIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0) Product: SIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0) Product: SIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0) Product: SIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0) Product: SIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0) Product: SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0) Product: SIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0) Product: SIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0) Product: SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0) Product: SIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0) Product: SIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0)

Summary

Siemens ET 200 devices contain a denial-of-service vulnerability that could be triggered by sending a valid S7 protocol Disconnect Request (COTP DR TPDU), causing the device to become unresponsive and require a power cycle to recover.

Siemens has released new versions for several affected products and recommends to update to the latest versions. Siemens is preparing further fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.

Vulnerabilities 1

Revision history

  1. #3

    Added fix for SIMATIC ET 200SP IM 155-6 PN/2 HF

  2. #2

    Added Researcher to Acknowledgements

  3. #1

    Publication Date

References