CVE-2025-40771Network attack vector

Configuration data access via unauthenticated connections

Published Oct 14, 2025 · Updated Oct 14, 2025

Missing authentication in Siemens SIMATIC ET 200SP communication processors before 2.4.24 allows remote attackers to access configuration data. The devices accept configuration connections without properly authenticating the connecting party, exposing configuration data to unauthenticated requests. Network reachability to a processor is sufficient; Siemens has not disclosed the configuration protocol or request sequence.

CVSS severity9.8
Critical
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in Siemens SIMATIC ET 200SP communication processors before 2.4.24 allows remote attackers to access configuration data. The devices accept configuration connections without properly authenticating the connecting party, exposing configuration data to unauthenticated requests. Network reachability to a processor is sufficient; Siemens has not disclosed the configuration protocol or request sequence.

The record

CVE
CVE-2025-40771
Published
Oct 14, 2025
Updated
Oct 14, 2025
Vendor
Siemens
Product
SIMATIC CP 1542SP-1
Classifications
CWE-306, T0882, T0866
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 14, 2025CVE publishedPublication date reported by the CVE source.
  2. Oct 14, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <V2.4.24

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Siemens · SIMATIC CP 1542SP-1version=0 <V2.4.24
Siemens · SIMATIC CP 1543SP-1version=0 <V2.4.24
Siemens · SIMATIC CP 1542SP-1 IRCversion=0 <V2.4.24
Siemens · SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAILversion=0 <V2.4.24
Siemens · SIPLUS ET 200SP CP 1543SP-1 ISECversion=0 <V2.4.24
Siemens · SIPLUS ET 200SP CP 1542SP-1 IRC TX RAILversion=0 <V2.4.24

Published CVSS scores

9.3Siemens AGCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8Siemens AGCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T0882Theft of Operational Information
T0866Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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