CVE-2023-43505Network attack vector

Authenticated file access via SMB share authorization failure

Published Nov 14, 2023 · Updated Jan 8, 2025

Improper access control in Siemens COMOS all versions allows remote authenticated users to access files through SMB shares. SMB share authorization checks fail to enforce the requesting user's permitted file scope, exposing files assigned to other users. Exploitation requires network access and valid low-privilege credentials; the advisory reports unauthorized read and write access impacts but no service interruption.

CVSS severity9.6
Critical
EPSS probability0.62%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Siemens COMOS all versions allows remote authenticated users to access files through SMB shares. SMB share authorization checks fail to enforce the requesting user's permitted file scope, exposing files assigned to other users. Exploitation requires network access and valid low-privilege credentials; the advisory reports unauthorized read and write access impacts but no service interruption.

The record

CVE
CVE-2023-43505
Published
Nov 14, 2023
Updated
Jan 8, 2025
Vendor
Siemens
Product
COMOS
Classifications
CWE-284, T1021.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 8, 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=All versions

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Siemens · COMOSversion=All versions

Published CVSS scores

9.6Siemens AGCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
6.5NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
9.6Siemens AGCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N/E:P/RL:O/RC:C

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1021.002SMB/Windows Admin Shares

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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