CyberSecBulletin
CVE-2025-40594NVD status: Modified

SINAMICS G220 V6.4: Improper Privilege Management

Published Updated By the CyberSecBulletin desk

CVE-2025-40594 is a critical-severity improper privilege management vulnerability in SINAMICS G220 V6.4 from Siemens, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version V6.4 HF2 as the first without the flaw, so updating SINAMICS G220 V6.4 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.21% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update SINAMICS G220 V6.4 to V6.4 HF2 or a later version.
  2. Update SINAMICS S200 V6.4 to V6.4 HF7 or a later version.
  3. Update SINAMICS S210 V6.4 to V6.4 HF2 or a later version.
  4. Read the advisory on cert-portal.siemens.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
SiemensSINAMICS G220 V6.4before V6.4 HF2V6.4 HF2
SiemensSINAMICS S200 V6.4before V6.4 HF7V6.4 HF7
SiemensSINAMICS S210 V6.4before V6.4 HF2V6.4 HF2
SiemensSinamics G220 Firmware6.4Not stated
SiemensSinamics S200 Firmware6.4Not stated
SiemensSinamics S210 Firmware6.4Not stated

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
NetworkCan be exploited remotely over a network, including the internet.
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
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.06.9MediumCNA (siemens.com)
CVSS 3.16.3MediumCNA (siemens.com)
CVSS 3.19.8CriticalNVD

Official description

A vulnerability has been identified in SINAMICS G220 V6.4 (All versions < V6.4 HF2), SINAMICS S200 V6.4 (All versions < V6.4 HF7), SINAMICS S210 V6.4 (All versions < V6.4 HF2). The affected devices allow a factory reset to be executed without the required privileges due to improper privilege management as well as manipulation of configuration data because of leaked privileges of previous sessions. This could allow an unauthorized attacker to escalate their privileges.

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

The underlying weakness: Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.

More Improper Privilege Management vulnerabilities (CWE-269)

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

Recent Improper Privilege Management vulnerabilities

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