Affected products do not properly enforce TCP sequence number validation in specific scenarios but accept values within a broad range. This could allow an unauthenticated remote attacker e.g. to interfere with connection setup, potentially leading to a denial of service. The attack succeeds only if an attacker can inject IP packets with spoofed addresses at precisely timed moments, and it affects only TCP-based services.

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable yes

Technical Impact partial

Affected Vendors & Products

Vendors Products
Siemens
  • Sidoor Atd430w
  • Sidoor Ate530s Coated
  • Simatic
  • Simatic Cfc
  • Simatic Cfu Diq
  • Simatic Cfu Pa
  • Simatic Et200al Im 157-1 Pn
  • Simatic Et200sp Im155-6 Mf Hf
  • Simatic Et 200mp Im 155-5 Pn Hf
  • Simatic Et 200s
  • Simatic Pcs
  • Simatic Pdm
  • Simatic S7-1500 Cpu 1510sp-1 Pn
  • Simatic S7-1500 Cpu 1510sp F-1 Pn
  • Simatic S7-1500 Cpu 1512sp-1 Pn
  • Simatic S7-1500 Cpu 1512sp F-1 Pn

No data.

No data.

References
Link Providers
https://cert-portal.siemens.com/productcert/html/ssa-915282.html cve-icon cve-icon
History

Wed, 10 Dec 2025 18:00:00 +0000

Type Values Removed Values Added
First Time appeared Siemens
Siemens sidoor Atd430w
Siemens sidoor Ate530s Coated
Siemens simatic
Siemens simatic Cfc
Siemens simatic Cfu Diq
Siemens simatic Cfu Pa
Siemens simatic Et200al Im 157-1 Pn
Siemens simatic Et200sp Im155-6 Mf Hf
Siemens simatic Et 200mp Im 155-5 Pn Hf
Siemens simatic Et 200s
Siemens simatic Pcs
Siemens simatic Pdm
Siemens simatic S7-1500 Cpu 1510sp-1 Pn
Siemens simatic S7-1500 Cpu 1510sp F-1 Pn
Siemens simatic S7-1500 Cpu 1512sp-1 Pn
Siemens simatic S7-1500 Cpu 1512sp F-1 Pn
Vendors & Products Siemens
Siemens sidoor Atd430w
Siemens sidoor Ate530s Coated
Siemens simatic
Siemens simatic Cfc
Siemens simatic Cfu Diq
Siemens simatic Cfu Pa
Siemens simatic Et200al Im 157-1 Pn
Siemens simatic Et200sp Im155-6 Mf Hf
Siemens simatic Et 200mp Im 155-5 Pn Hf
Siemens simatic Et 200s
Siemens simatic Pcs
Siemens simatic Pdm
Siemens simatic S7-1500 Cpu 1510sp-1 Pn
Siemens simatic S7-1500 Cpu 1510sp F-1 Pn
Siemens simatic S7-1500 Cpu 1512sp-1 Pn
Siemens simatic S7-1500 Cpu 1512sp F-1 Pn

Tue, 09 Dec 2025 16:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 09 Dec 2025 11:00:00 +0000

Type Values Removed Values Added
Description Affected products do not properly enforce TCP sequence number validation in specific scenarios but accept values within a broad range. This could allow an unauthenticated remote attacker e.g. to interfere with connection setup, potentially leading to a denial of service. The attack succeeds only if an attacker can inject IP packets with spoofed addresses at precisely timed moments, and it affects only TCP-based services.
Weaknesses CWE-940
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}
cve-icon MITRE

Status: PUBLISHED

Assigner: siemens

Published: 2025-12-09T10:44:30.977Z

Updated: 2025-12-09T15:55:23.400Z

Reserved: 2025-04-16T08:50:26.975Z

Link: CVE-2025-40820

cve-icon Vulnrichment

Updated: 2025-12-09T15:55:01.982Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-12-09T16:17:46.413

Modified: 2025-12-09T18:36:53.557

Link: CVE-2025-40820

cve-icon Redhat

No data.