Siemens SIMATIC ET 200AL IM 157-1 PN resource consumption

Summaryinfo

A vulnerability classified as problematic has been found in Siemens SIMATIC ET 200AL IM 157-1 PN, SIMATIC ET 200MP IM 155-5 PN HF, SIMATIC ET 200SP IM 155-6 MF HF, SIMATIC ET 200SP IM 155-6 PN HA, SIMATIC ET 200SP IM 155-6 PN R1, SIMATIC ET 200SP IM 155-6 PN, 2 HF, 3 HF, SIMATIC PN, MF Coupler, PN Coupler, SIPLUS ET 200MP IM 155-5 PN HF, SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL, SIPLUS ET 200SP IM 155-6 PN HF, SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL, SIPLUS ET 200SP IM 155-6 PN HF TX RAIL and SIPLUS NET PN. This vulnerability affects unknown code. Performing a manipulation results in resource consumption. This vulnerability was named CVE-2025-40944. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Siemens SIMATIC ET 200AL IM 157-1 PN, SIMATIC ET 200MP IM 155-5 PN HF, SIMATIC ET 200SP IM 155-6 MF HF, SIMATIC ET 200SP IM 155-6 PN HA, SIMATIC ET 200SP IM 155-6 PN R1, SIMATIC ET 200SP IM 155-6 PN, 2 HF, 3 HF, SIMATIC PN, MF Coupler, PN Coupler, SIPLUS ET 200MP IM 155-5 PN HF, SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL, SIPLUS ET 200SP IM 155-6 PN HF, SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL, SIPLUS ET 200SP IM 155-6 PN HF TX RAIL and SIPLUS NET PN. This affects some unknown processing. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. This is going to have an impact on availability. The summary by CVE is:

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 = V4.2.0), SIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0) (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.

It is possible to read the advisory at cert-portal.siemens.com. This vulnerability is uniquely identified as CVE-2025-40944 since 04/16/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/13/2026). The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• SCADA Software

Vendor

• Siemens

Name

• 2 HF
• 3 HF
• MF Coupler
• PN Coupler
• SIMATIC ET 200AL IM 157-1 PN
• SIMATIC ET 200MP IM 155-5 PN HF
• SIMATIC ET 200SP IM 155-6 MF HF
• SIMATIC ET 200SP IM 155-6 PN
• SIMATIC ET 200SP IM 155-6 PN HA
• SIMATIC ET 200SP IM 155-6 PN R1
• SIMATIC PN
• SIPLUS ET 200MP IM 155-5 PN HF
• SIPLUS ET 200MP IM 155-5 PN HF T1 RAIL
• SIPLUS ET 200SP IM 155-6 PN HF
• SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL
• SIPLUS ET 200SP IM 155-6 PN HF TX RAIL
• SIPLUS NET PN

License

• commercial

Website

• Vendor: https://www.siemens.com/

CPE 2.3info

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Entryinfo

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