OpenflowApplication · Opennetworking

CVE-2018-1000155

CRITICAL · 9.8 CVSS v3.0 Published 2018-05-24
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
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
OpenFlow version 1.0 onwards contains a Denial of Service and Improper authorization vulnerability in OpenFlow handshake: The DPID (DataPath IDentifier) in the features_reply message are inherently trusted by the controller. that can result in Denial of Service, Unauthorized Access, Network Instability. This attack appear to be exploitable via Network connectivity: the attacker must first establish a transport connection with the OpenFlow controller and then initiate the OpenFlow handshake.

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

OpenFlow version 1.0 and later suffers from improper validation of the DataPath Identifier (DPID) in features_reply messages during the OpenFlow handshake. The controller inherently trusts the DPID supplied by incoming switch connections without verification, allowing an authenticated attacker who completes the handshake to trigger denial of service, gain unauthorized access to controller functions, or cause network instability.

MitigationImplement strict DPID validation and authentication checks in the controller before trusting any features_reply data; reject connections from untrusted or unauthenticated switch sources at the transport layer to prevent handshake completion by attackers.

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

CVSS:3.0/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. Confirm OpenFlow controller is exposed
    Identify if an OpenFlow controller service (such as Open Networking Foundation OpenFlow) is running and listening on the network. Check for services on well-known OpenFlow ports (6653, 6633) or custom ports configured in your environment.
    Affected if An OpenFlow controller is active and accepting connections from network switches.
  2. Verify switch authentication is enforced
    Review controller configuration files and access control settings to determine whether incoming switch connections require authentication before the OpenFlow handshake completes. Look for ACLs, TLS certificates, or pre-shared key configurations.
    Affected if The controller allows unauthenticated or unauthenticated switch connections to proceed to the features_reply phase of the handshake.
  3. Inspect DPID validation logic
    Examine controller source code or configuration for validation routines that verify the DataPath Identifier (DPID) in incoming features_reply messages against expected or registered values.
    Affected if The controller does not validate or verify DPID values before trusting them in switch session handling.
  4. Check for trusted switch allowlists
    Review controller configuration for whitelists or access control lists that explicitly define which DPIDs or switch MAC addresses are permitted to connect.
    Affected if No DPID or switch source allowlist is configured, allowing arbitrary DPID values in features_reply messages.
  5. Review logs for anomalous handshake behavior
    Examine controller logs for features_reply messages containing unexpected or duplicate DPIDs, connection attempts from unknown switches, or handshake anomalies.
    Affected if Logs show features_reply messages with DPIDs that were not pre-registered or validated.

A user is affected if they run an OpenFlow controller that accepts connections without authenticating switches and without validating the DPID supplied in features_reply messages before trusting it.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict DPID validation and authentication checks in the controller before trusting any features_reply data; reject connections from untrusted or unauthenticated switch sources at the transport layer to prevent handshake completion by attackers.

Fix this in Openflow Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
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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-2018-1000155 in production — separate from our analysis above.

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What this is

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