CVE-2022-47374Network attack vector

Service interruption via recursive HTTP request handling

Published Dec 12, 2023 · Updated Feb 25, 2026

Uncontrolled recursion in Siemens SIMATIC, SIPLUS, and SINAMICS web servers allows remote attackers to exhaust resources and interrupt service. Siemens attributes the flaw to uncontrolled recursion in HTTP(S) request handling but does not disclose the recursive code path or request shape. Network access to an enabled web server is sufficient; the documented consequence is service interruption, with no confidentiality or integrity impact.

CVSS severity7.5
High
EPSS probability0.72%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled recursion in Siemens SIMATIC, SIPLUS, and SINAMICS web servers allows remote attackers to exhaust resources and interrupt service. Siemens attributes the flaw to uncontrolled recursion in HTTP(S) request handling but does not disclose the recursive code path or request shape. Network access to an enabled web server is sufficient; the documented consequence is service interruption, with no confidentiality or integrity impact.

The record

CVE
CVE-2022-47374
Published
Dec 12, 2023
Updated
Feb 25, 2026
Vendor
Siemens
Product
SIMATIC S7-400 CPU 416F-3 PN/DP
Classifications
CWE-674, T0814
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 12, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 25, 2026Record 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=All versions

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Siemens · SIMATIC S7-400 CPU 416F-3 PN/DPversion=All versions
Siemens · SINAMICS S120version=All versions < V5.2 SP3 HF15
Siemens · SIMATIC S7-400 CPU 416-3 PN/DP V7version=All versions
Siemens · SIMATIC PC-Station Plusversion=All versions
Siemens · SIPLUS S7-400 CPU 416-3 PN/DPversion=All versions
Siemens · SIPLUS S7-400 CPU 414-3 PN/DP V7version=All versions
Siemens · SIMATIC S7-400 CPU 414-3 PN/DP V7version=All versions
Siemens · SIMATIC S7-400 CPU 414F-3 PN/DP V7version=All versions
Siemens · SIMATIC S7-400 CPU 412-2 PN V7version=All versions

Published CVSS scores

7.5Siemens AGCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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.

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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-674Uncontrolled Recursion
T0814Denial of Service

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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