dbcve.org
6md85 FirmwareOperating system · Siemens

CVE-2021-41769

HIGH · 7.5 CVSS v3.1 Published 2022-01-11
Fix available
A fix is available. Upgrade to 8.83 or later.
See remediation →
84/100
Remediation priority · High
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
A vulnerability has been identified in SIPROTEC 5 6MD85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 6MD86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 6MD89 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 6MU85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7KE85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SA82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SA86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SA87 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SD82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SD86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SD87 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SJ81 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SJ82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SJ85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SJ86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SK82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SK85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SL82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7SL86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SL87 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SS85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7ST85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7SX85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7UM85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7UT82 devices (CPU variant CP100) (All versions < V8.83), SIPROTEC 5 7UT85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7UT86 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7UT87 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7VE85 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 7VK87 devices (CPU variant CP300) (All versions < V8.83), SIPROTEC 5 Compact 7SX800 devices (CPU variant CP050) (All versions < V8.83). An improper input validation vulnerability in the web server could allow an unauthenticated user to access device information.

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

An improper input validation vulnerability exists in the web server component of Siemens SIPROTEC 5 devices. This flaw allows an unauthenticated remote attacker to bypass authentication and access sensitive device information without credentials. The vulnerability stems from insufficient validation of input parameters in the web interface, enabling directory traversal or similar manipulation to retrieve device data.

MitigationUpgrade all affected SIPROTEC 5 devices to firmware version V8.83 or later. Until patches are applied, restrict network access to the web server interface using firewalls or VLANs, and disable the web server if not operationally required.

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
6md85 FirmwareOperating system
Affected:< 8.83
6md86 FirmwareOperating system
Affected:< 8.83
6md89 FirmwareOperating system
Affected:< 8.83
6mu85 FirmwareOperating system
Affected:< 8.83
7ke85 FirmwareOperating system
Affected:< 8.83
7sa82 FirmwareOperating system
Affected:< 8.83
7sa86 FirmwareOperating system
Affected:< 8.83
7sa87 FirmwareOperating system
Affected:< 8.83

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
None
Availability
None

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

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 SIPROTEC 5 device model
    Locate the device label, check the device inventory, or access the web interface to identify the exact model number (6md85, 6md86, 6md89, 6mu85, 7ke85, 7sa82, 7sa86, or 7sa87)
    Affected if The device model is one of the eight listed variants
  2. Check the installed firmware version
    Access the device web interface and navigate to the firmware or device information section, or use the device management software to retrieve the firmware version
    Affected if The firmware version is below 8.83 (for example, 8.80, 8.81, 8.82)
  3. Confirm the web server interface is enabled
    Check the device configuration settings for the web server status, typically found under communication settings or web server configuration in the device web interface or management software
    Affected if The web server is enabled and accessible on the network
  4. Verify network accessibility of the web interface
    Determine if the device web server port (typically HTTP port 80 or HTTPS port 443) is exposed to the network by checking firewall rules, VLAN configurations, or performing a port scan of the device IP address
    Affected if The web interface is reachable from network segments accessible to untrusted users
  5. Review access logs for directory traversal attempts
    Examine the device web server logs or security event logs for suspicious patterns such as requests containing ../ sequences, encoded path characters, or unauthorized access to sensitive device configuration files
    Affected if Log entries show directory traversal patterns or unauthorized access to sensitive device data without valid authentication

You are affected if your device model is one of the listed SIPROTEC 5 variants, the web server is enabled, and the firmware version is below 8.83.

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 8.83 or later
Fixed in 8.83
Interim mitigation

Upgrade all affected SIPROTEC 5 devices to firmware version V8.83 or later. Until patches are applied, restrict network access to the web server interface using firewalls or VLANs, and disable the web server if not operationally required.

Recommended fix High confidence

Firmware V8.83 or later for SIPROTEC 5 devices

  1. 1. Identify the exact SIPROTEC 5 device model (e.g., 6MD85, 7SA86, etc.) and its current CPU variant (CP100 or CP300) from the device label or management interface.
  2. 2. Check the current firmware version by accessing the device's web interface or using Siemens DIGSI software.
  3. 3. Obtain the firmware version V8.83 or later from the Siemens support portal (cert-portal.siemens.com) or official Siemens customer support.
  4. 4. Before upgrading, review Siemens upgrade documentation and ensure you have a backup of the device configuration.
  5. 5. Perform the firmware upgrade following Siemens standard procedures - typically via the device web interface (Device > Firmware Update) or using DIGSI software.
  6. 6. After the upgrade completes, verify the device is running firmware V8.83 or later.
  7. 7. Confirm the vulnerability is remediated by verifying that the web server now properly validates input and unauthenticated access to device information is no longer possible.

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

Fix this in 6md85 Firmware Scoped from the published advisory
  • Consultation6.0 h
  • Implementation12.0 h
  • Testing8.0 h
  • Review / QA4.0 h
30.0 hours of engineering $5,280
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,448.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-41769 — 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-2021-41769 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