Simatic S7 1200 FirmwareOperating system · Siemens

CVE-2018-13815

HIGH · 7.5 CVSS v3.0 Published 2018-12-13
Fix available
A fix is available. Upgrade to 2.6 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 SIMATIC S7-1200 (All versions), SIMATIC S7-1500 (All Versions < V2.6). An attacker could exhaust the available connection pool of an affected device by opening a sufficient number of connections to the device. Successful exploitation requires an attacker to be able to send packets to port 102/tcp of the affected device. No user interaction and no user privileges are required to exploit the vulnerability. The vulnerability, if exploited, could cause a Denial-of-Service condition impacting the availability of the system. At the time of advisory publication no public exploitation of this vulnerability was known.

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 vulnerability allows remote attackers to exhaust the available connection pool on affected SIMATIC S7-1200 and S7-1500 devices by opening numerous connections to port 102/tcp (S7comm protocol), causing a denial-of-service condition that renders the device unavailable.

MitigationUpdate SIMATIC S7-1500 to firmware version 2.6 or later; for S7-1200 (no patch available per advisory) or as additional defense, implement network segmentation and firewall rules to restrict access to port 102/tcp to authorized systems only.

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 1200 FirmwareOperating system
Affected:all versions
Simatic S7 1500 FirmwareOperating system
Affected:< 2.6

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
None
Integrity
None
Availability
High

CVSS:3.0/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 device model
    Query the device via S7comm protocol or check device documentation/management interface to confirm whether it is a Simatic S7-1200 or S7-1500 PLC
    Affected if Device is a Simatic S7-1200 (all versions affected) or S7-1500 with firmware below 2.6
  2. Check S7-1500 firmware version
    Access the device web interface, TIA Portal project, or use S7comm GetSZL request (SZL ID 0x0011, 0x001C) to read the firmware version
    Affected if Firmware version is below 2.6 on S7-1500 devices (S7-1200 has no patch so all versions are affected)
  3. Verify port 102/tcp exposure
    Scan network perimeter or use netstat/ss commands on adjacent devices to confirm whether port 102/tcp is reachable from untrusted networks or the internet
    Affected if Port 102/tcp is exposed to untrusted or external networks without firewall filtering
  4. Check for connection pool exhaustion
    Monitor device response time, attempt S7comm connection, or check device logs for connection refused errors; look for symptoms of resource exhaustion
    Affected if Device becomes unresponsive to new S7comm connections or shows connection timeout errors

You are affected if the device is an S7-1200 (any firmware) or S7-1500 with firmware below 2.6, and port 102/tcp is accessible to untrusted networks.

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 2.6 or later
Fixed in 2.6
Interim mitigation

Update SIMATIC S7-1500 to firmware version 2.6 or later; for S7-1200 (no patch available per advisory) or as additional defense, implement network segmentation and firewall rules to restrict access to port 102/tcp to authorized systems only.

Fix this in Simatic S7 1200 Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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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-2018-13815 in production — separate from our analysis above.

No notes yet

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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