CVE-2025-40944

highpriority · track · 0EPSS 0.004 · 37 %ileDEEUNLUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.44% (37th) EPSS
CVSS 7.5 · high
Is it mine?
189 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · cisa_csaf_ot · ncsc_nl

EPSS · scored 2026-10-22

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 < V4.2.5), 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 < V4.2.5), SIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0) (All versions >= V4.2.0 < V4.2.5), SIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0) (All versions >= V4.2.0 < V4.2.5), SIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0) (All versions >= V4.2.0 < V4.2.5), 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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • FixedSIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants)siemens_psirt

    Update to V1.3 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109987451/
  • FixedSIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0)siemens_psirt

    Update to V6.0.1 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109816000/
  • FixedSIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0)siemens_psirt

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0)siemens_psirt

    Update to V4.2.2 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769419/
  • FixedSIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0)siemens_psirt

    Update to V6.0.0 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109760973/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0)siemens_psirt

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0)siemens_psirt

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0)siemens_psirt

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0)siemens_psirt

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0)siemens_psirt

    Update to V6.0.0 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109760973/
  • FixedSIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants)cisa_csaf_ot

    Update to V1.3 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109987451/
  • FixedSIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0)cisa_csaf_ot

    Update to V6.0.1 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109816000/
  • FixedSIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0)cisa_csaf_ot

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0)cisa_csaf_ot

    Update to V4.2.2 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769419/
  • FixedSIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0)cisa_csaf_ot

    Update to V6.0.0 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109760973/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0)cisa_csaf_ot

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0)cisa_csaf_ot

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0)cisa_csaf_ot

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0)cisa_csaf_ot

    Update to V4.2.5 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109769765/
  • FixedSIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0)cisa_csaf_ot

    Update to V6.0.0 or later version

    https://support.industry.siemens.com/cs/ww/en/view/109760973/
  • MitigationSIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0)siemens_psirt

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN HA (incl. SIPLUS variants)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN R1 (6ES7155-6AU00-0HM0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN/2 HF (6ES7155-6AU01-0CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC ET 200SP IM 155-6 PN/3 HF (6ES7155-6AU30-0CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIMATIC PN/PN Coupler (6ES7158-3AD10-0XA0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-2CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF (6AG1155-6AU01-7CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF T1 RAIL (6AG2155-6AU01-1CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS ET 200SP IM 155-6 PN HF TX RAIL (6AG2155-6AU01-4CN0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • MitigationSIPLUS NET PN/PN Coupler (6AG2158-3AD10-4XA0)cisa_csaf_ot

    Filter the port 102 of the devices to only accepted connections to/from the IP addresses of machines that are trusted e.g. with an external firewall.

  • No fix plannedSIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0)siemens_psirt

    Currently no fix is planned

  • No fix plannedSIMATIC ET 200AL IM 157-1 PN (6ES7157-1AB00-0AB0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIMATIC ET 200MP IM 155-5 PN HF (6ES7155-5AA00-0AC0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIMATIC ET 200SP IM 155-6 MF HF (6ES7155-6MU00-0CN0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIMATIC PN/MF Coupler (6ES7158-3MU10-0XA0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-2AC0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF (6AG1155-5AA00-7AC0)cisa_csaf_ot

    Currently no fix is planned

  • No fix plannedSIPLUS ET 200MP IM 155-5 PN HF T1 RAIL (6AG2155-5AA00-1AC0)cisa_csaf_ot

    Currently no fix is planned

02

cvss

Technical severity, 0–10. One row per scoring source.

8.7
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–8.7

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · productcert@siemens.com DEexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Siemens ProductCERT DE
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · NCSC-NL NL
v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU
v4.08.7highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · productcert@siemens.com DE
v4.06.6mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USCWE-400USCWE-400USCWE-400US
05

affected products (189)

Products and version ranges known to be affected.

showing 20 of 189
06

advisories (3)

Vendor and ecosystem advisories describing this.

  • NCSC-2026-0005Kwetsbaarheden verholpen in Siemens productenNL2026-01-13csaf · ncsc_nlNL

    Siemens heeft kwetsbaarheden verholpen in diverse producten als Industrial Edge Devices, SCALANCE, SIMATIC, SIPLUS en Telecontrol Server.

  • SSA-674753SSA-674753: Denial-of-Service Vulnerability in ET 200 Devices2026-01-13csaf · siemens_psirtDE

    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.

  • ICSA-26-015-04Siemens SIMATIC and SIPLUS products2026-01-13icsa · cisa_csaf_otUS

    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.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdcisa_csaf_otncsc_nlsiemens_psirtNVDCVE.orgMITRE
published 2026-01-13modified 2026-06-17
09

references (4)

External citations — patches, advisories, analysis.

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