Simatic S7 200 FirmwareOperating system · Siemens

CVE-2017-12741

HIGH · 7.5 CVSS v3.1 Published 2017-12-26
Fix available
A fix is available. Upgrade to 2.0 / 2.03.01 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
Specially crafted packets sent to port 161/udp could cause a denial of service condition. The affected devices must be restarted manually.

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 · moderate confidence

A denial of service vulnerability in the SNMP service (port 161/UDP) allows specially crafted packets to crash affected devices, requiring manual restart to recover.

MitigationRestrict access to UDP port 161 from untrusted networks using firewall rules or ACLs; if SNMP is not required, disable the service entirely.

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
Simatic S7 200 FirmwareOperating system
Affected:< 2.03.01
Simatic S7 400pn V6 FirmwareOperating system
Affected:< 6.0.6
Simatic S7 400h V6 FirmwareOperating system
Affected:< 6.0.8
Simatic S7 400pn\/dp V7 FirmwareOperating system
Affected:all versions
Simatic S7 410 V8 FirmwareOperating system
Affected:all versions
Simatic S7 300 FirmwareOperating system
Affected:all versions
Simatic S7 1200 FirmwareOperating system
Affected:all versions
Simatic S7 1500 FirmwareOperating system
Affected:< 2.0

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
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 Simatic S7 device model
    Locate the device labeling or access the device properties via TIA Portal or web interface to determine the exact model (S7-200, S7-400pn V6, S7-400h V6, S7-400pn/dp V7, S7-410 V8, S7-300, S7-1200, or S7-1500)
    Affected if The device is any Simatic S7 model listed in the affected products
  2. Determine the installed firmware version
    Access the device via TIA Portal, Step 7, or the device's web interface to read the current firmware version
    Affected if The firmware version falls within the affected ranges: S7-200 < 2.03.01, S7-400pn V6 < 6.0.6, S7-400h V6 < 6.0.8, S7-400pn/dp V7 all versions, S7-410 V8 all versions, S7-300 all versions, S7-1200 all versions, S7-1500 < 2.0
  3. Verify if SNMP service is enabled
    Check the device configuration in TIA Portal or Step 7 under the device properties for SNMP settings, or scan UDP port 161 from the network to confirm the service is listening
    Affected if SNMP service is enabled and UDP port 161 is open and accessible on the device
  4. Confirm network accessibility of SNMP port
    Perform a UDP port scan targeting port 161 on the device IP address to determine if the SNMP service is reachable from your network segment
    Affected if UDP port 161 responds to SNMP queries, indicating the vulnerable service is exposed

The environment is affected if the device is a Siemens Simatic S7 model with a firmware version within the affected ranges and SNMP service on UDP port 161 is enabled and accessible.

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.

From vendor data
Upgrade available Upgrade to 2.0 / 2.03.01 / 6.0.6 or later
Fixed in 2.02.03.016.0.6
Interim mitigation

Restrict access to UDP port 161 from untrusted networks using firewall rules or ACLs; if SNMP is not required, disable the service entirely.

Fix this in Simatic S7 200 Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2017-12741 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2017-12741 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