dbcve.org
Apu0200 FirmwareOperating system · Sick

CVE-2023-43696

CRITICAL · 9.8 CVSS v3.1 Published 2023-10-09
Fix available
A fix is available. Upgrade to 4.0.0.6 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
Improper Access Control in SICK APU allows an unprivileged remote attacker to download as well as upload arbitrary files via anonymous access to the FTP server.

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

The SICK APU device has an FTP server that allows anonymous access without any access controls. An unprivileged remote attacker can exploit this to download arbitrary files from the device's filesystem and upload arbitrary files to the device, potentially enabling data exfiltration, firmware tampering, or further network compromise.

MitigationDisable anonymous FTP access on the SICK APU device, implement proper authentication for FTP connections, and restrict FTP operations to authorized users with appropriate file system permissions. Consider disabling FTP entirely and using secure file transfer protocols if possible.

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
Apu0200 FirmwareOperating system
Affected:< 4.0.0.6

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
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 the firmware version of the SICK APU device
    Access the device management interface or check the device configuration to retrieve the current firmware version. This is typically found in the device status or system information section of the web UI or through the device's CLI.
    Affected if The installed firmware version is Apu0200 and is lower than 4.0.0.6
  2. Verify if the FTP server is enabled on the device
    Check the device's service configuration or network settings to determine whether the FTP server feature is currently active. Look for FTP server settings in the device administration panel.
    Affected if FTP server is enabled and running on the device
  3. Confirm the FTP anonymous access configuration
    Examine the FTP server settings to determine if anonymous or unauthenticated FTP connections are permitted. This usually involves checking the FTP service configuration for any 'anonymous' or 'guest' user settings or authentication requirements.
    Affected if Anonymous FTP access is allowed (no authentication required to connect)

You are affected if your SICK Apu0200 device runs firmware below version 4.0.0.6, has FTP enabled, and permits anonymous FTP access without requiring credentials.

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 4.0.0.6 or later
Fixed in 4.0.0.6
Interim mitigation

Disable anonymous FTP access on the SICK APU device, implement proper authentication for FTP connections, and restrict FTP operations to authorized users with appropriate file system permissions. Consider disabling FTP entirely and using secure file transfer protocols if possible.

Recommended fix High confidence

APU0200 Firmware 4.0.0.6 or later

  1. 1. Identify the current firmware version of the SICK APU (Apu0200) by accessing the device management interface or checking system information.
  2. 2. Navigate to the official SICK support website (sick.com) and locate the firmware download section for the APU0200 device.
  3. 3. Download firmware version 4.0.0.6 or later from SICK's official support page.
  4. 4. Access the device's firmware update mechanism, typically via the web-based management interface or FTP server.
  5. 5. Upload and apply the new firmware version following SICK's documented firmware upgrade procedure.
  6. 6. After the upgrade completes, verify that the firmware version has been updated to 4.0.0.6 or higher.
  7. 7. Confirm that anonymous FTP access has been properly restricted in the new firmware configuration.
  8. 8. Test that only authenticated users can access FTP functionality and that file operations require proper authorization.

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

Fix this in Apu0200 Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,390
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,224.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-43696 — 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-2023-43696 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