CyberSecBulletin
CVE-2025-40816NVD status: Deferred

LOGO! 12/24RCE: Missing Authentication for Critical Functionality

Published Updated By the CyberSecBulletin desk

CVE-2025-40816 is a high-severity missing authentication for critical functionality vulnerability in LOGO! 12/24RCE from Siemens, with a CVSS 3.1 base score of 7.6 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists version V1.84.05 as the first without the flaw, so updating LOGO! 12/24RCE to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update LOGO! 12/24RCE to V1.84.05 or a later version.
  2. Update LOGO! 12/24RCEo to V1.84.05 or a later version.
  3. Update LOGO! 230RCE to V1.84.05 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
SiemensLOGO! 12/24RCEbefore V1.84.05V1.84.05
SiemensLOGO! 12/24RCEobefore V1.84.05V1.84.05
SiemensLOGO! 230RCEbefore V1.84.05V1.84.05
SiemensLOGO! 230RCEobefore V1.84.05V1.84.05
SiemensLOGO! 24CEbefore V1.84.05V1.84.05
SiemensLOGO! 24CEobefore V1.84.05V1.84.05
SiemensLOGO! 24RCEbefore V1.84.05V1.84.05
SiemensLOGO! 24RCEobefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 12/24RCEbefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 12/24RCEobefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 230RCEbefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 230RCEobefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 24CEbefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 24CEobefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 24RCEbefore V1.84.05V1.84.05
SiemensSIPLUS LOGO! 24RCEobefore V1.84.05V1.84.05

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
LowSome restricted data can be read.
Integrity
LowLimited modification of data is possible.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H. Scored by CNA (siemens.com).

Scoring systemScoreSeverityScored by
CVSS 4.07.2HighCNA (siemens.com)
CVSS 3.17.6HighCNA (siemens.com)

Official description

A vulnerability has been identified in LOGO! 12/24RCE (6ED1052-1MD08-0BA2) (All versions < V1.84.05), LOGO! 12/24RCEo (6ED1052-2MD08-0BA2) (All versions < V1.84.05), LOGO! 230RCE (6ED1052-1FB08-0BA2) (All versions < V1.84.05), LOGO! 230RCEo (6ED1052-2FB08-0BA2) (All versions < V1.84.05), LOGO! 24CE (6ED1052-1CC08-0BA2) (All versions < V1.84.05), LOGO! 24CEo (6ED1052-2CC08-0BA2) (All versions < V1.84.05), LOGO! 24RCE (6ED1052-1HB08-0BA2) (All versions < V1.84.05), LOGO! 24RCEo (6ED1052-2HB08-0BA2) (All versions < V1.84.05), SIPLUS LOGO! 12/24RCE (6AG1052-1MD08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 12/24RCEo (6AG1052-2MD08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 230RCE (6AG1052-1FB08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 230RCEo (6AG1052-2FB08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 24CE (6AG1052-1CC08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 24CEo (6AG1052-2CC08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 24RCE (6AG1052-1HB08-7BA2) (All versions < V1.84.05), SIPLUS LOGO! 24RCEo (6AG1052-2HB08-7BA2) (All versions < V1.84.05). Affected devices do not conduct certain validations when interacting with them. This could allow an unauthenticated remote attacker to manipulate the devices IP address, which means the device would not be reachable.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Missing Authentication for Critical Functionality

The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator.
  • When storing data in the cloud (e.g., S3 buckets, Azure blobs, Google Cloud Storage, etc.), use the provider's controls to require strong authentication for users who should be allowed to access the data.

More Missing Authentication for Critical Functionality vulnerabilities (CWE-306)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in LOGO! 12/24RCE

All LOGO! 12/24RCE vulnerabilities

Recent Missing Authentication for Critical Functionality vulnerabilities

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