dbcve.org
Sinamics S\/g Family FirmwareOperating system · Siemens

CVE-2013-6920

HIGH · 10.0 CVSS v2.0 Published 2013-12-07
Fix available
A fix is available. Upgrade to after 4.6 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Siemens SINAMICS S/G controllers with firmware before 4.6.11 do not require authentication for FTP and TELNET sessions, which allows remote attackers to bypass intended access restrictions via TCP traffic to port (1) 21 or (2) 23.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Siemens SINAMICS S/G controller firmware before version 4.6.11 ships with FTP (port 21) and TELNET (port 23) services that do not require authentication, allowing unauthenticated remote attackers to gain full access to these industrial control devices by connecting directly to these services.

MitigationUpdate SINAMICS S/G firmware to version 4.6.11 or later to enable authentication, or disable FTP and TELNET services entirely if not required and use alternative secure protocols.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Sinamics S\/g Family FirmwareOperating system
Affected:<= 4.6
Sinamics G110Hardware / appliance
Affected:all versions
Sinamics G110dHardware / appliance
Affected:all versions
Sinamics G120Hardware / appliance
Affected:all versions
Sinamics G120cHardware / appliance
Affected:all versions
Sinamics G120dHardware / appliance
Affected:all versions
Sinamics G120pHardware / appliance
Affected:all versions
Sinamics G130Hardware / appliance
Affected:all versions

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete

AV:N/AC:L/Au:N/C:C/I:C/A:C

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify your Sinamics device model
    Locate the device nameplate or check your asset inventory for the exact Sinamics model (e.g., G120, G130, S/G series)
    Affected if The device is any of: Sinamics G110, G110d, G120, G120c, G120d, G120p, G130, or S/G family
  2. Determine the installed firmware version
    Access the device control unit or use the Sinamics engineering tool (e.g., STARTER or Startdrive) to read the firmware version from the device properties
    Affected if Firmware version is 4.6 or lower for S/G family, or any version for G110/G130 series models
  3. Verify if FTP service is exposed
    Attempt a TCP connection to port 21 on the device IP address, or check network firewall rules allowing inbound traffic to port 21
    Affected if Port 21 is open and accepts FTP connections without prompting for credentials
  4. Verify if TELNET service is exposed
    Attempt a TCP connection to port 23 on the device IP address, or check network firewall rules allowing inbound traffic to port 23
    Affected if Port 23 is open and provides shell access without prompting for authentication

You are affected if your Sinamics device is any G110/G130 series (all versions) or S/G family with firmware <=4.6, AND either FTP (port 21) or TELNET (port 23) is accessible on the network without authentication.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to a release after 4.6
Interim mitigation

Update SINAMICS S/G firmware to version 4.6.11 or later to enable authentication, or disable FTP and TELNET services entirely if not required and use alternative secure protocols.

Recommended fix High confidence

SINAMICS S/G firmware 4.6.11 or later (contact Siemens for patched firmware for G-series devices)

  1. 1. Identify the specific Sinamics device model and its current firmware version by accessing the device or its management interface
  2. 2. For SINAMICS S/G controllers: Determine if the current firmware version is before 4.6.11 (vulnerable)
  3. 3. For SINAMICS G110, G110d, G120, G120c, G120d, G120p, G130: Note that all versions are affected; check Siemens for any available firmware updates
  4. 4. Download the patched firmware from Siemens support portal (cert-portal.siemens.com or siemens.com) - ensure the version is 4.6.11 or later for S/G
  5. 5. Follow Siemens' official firmware update procedure for your specific device model
  6. 6. After updating, verify the firmware version is 4.6.11 or higher
  7. 7. As a configuration mitigation: If FTP/TELNET are not required for operations, disable these services on the device
  8. 8. If these services are required, implement network segmentation to restrict access to trusted networks only
Caveat Standard firmware update risks apply - ensure backup of configuration and plan for potential downtime

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Sinamics S\/g Family Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
11.0 hours of engineering $2,000
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,200.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2013-6920 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2013-6920 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data