CVE-2025-40944 
A vulnerability has been identified in SIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0) (All versions), SIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0) (All versions >= V4.2.0), SIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0) (All versions), SIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants) (All versions < V1.3), SIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0) (All versions < V6.0.1), SIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0) (All versions >= V4.2.0), SIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0) (All versions < V4.2.2), SIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0) (All versions), SIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0) (All versions < V6.0.0), SIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0) (All versions >= V4.2.0), SIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0) (All versions >= V4.2.0), SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0) (All versions >= V4.2.0), SIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0) (All versions >= V4.2.0), SIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0) (All versions >= V4.2.0), SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0) (All versions >= V4.2.0), SIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0) (All versions >= V4.2.0), SIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0) (All versions < V6.0.0). Affected devices do not properly handle S7 protocol session disconnect requests. When receiving a valid S7 protocol Disconnect Request (COTP DR TPDU) on TCP port 102, the devices enter an improper session state.

This could allow an attacker to cause the device to become unresponsive, leading to a denial-of-service condition that requires a power cycle to restore normal operation.
Problem types: cwe_id: CWE-400
description: CWE-400: Uncontrolled Resource Consumption
Affected products: vendor: Siemens
product: SIMATIC ET 200AL IM 157-1 PN
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200MP IM 155-5 PN HF
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200SP IM 155-6 MF HF
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants)
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200SP IM 155-6 PN R1
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200SP IM 155-6 PN/2 HF
default_status: unknown
vendor: Siemens
product: SIMATIC ET 200SP IM 155-6 PN/3 HF
default_status: unknown
vendor: Siemens
product: SIMATIC PN/MF Coupler
default_status: unknown
vendor: Siemens
product: SIMATIC PN/PN Coupler
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200MP IM 155-5 PN HF
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200MP IM 155-5 PN HF
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200SP IM 155-6 PN HF
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200SP IM 155-6 PN HF
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL
default_status: unknown
vendor: Siemens
product: SIPLUS ET 200SP IM 155-6 PN HF TX RAIL
default_status: unknown
vendor: Siemens
product: SIPLUS NET PN/PN Coupler
default_status: unknown
CVSS v3.1: version: 3.1
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
baseScore: 7.5
baseSeverity: HIGH
Published: 2026-01-13T09:44:05.792Z