iOSOperating system · Cisco
CVE-2016-6403
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 · uneditedThe Data in Motion (DMo) application in Cisco IOS 15.6(1)T and IOS XE, when the IOx feature set is enabled, allows remote attackers to cause a denial of service via a crafted packet, aka Bug IDs CSCuy82904, CSCuy82909, and CSCuy82912.
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 confidenceThe Data in Motion (DMo) application in Cisco IOS 15.6(1)T and IOS XE contains a vulnerability when the IOx feature set is enabled. Remote attackers can send crafted packets to the affected device, causing a denial of service condition by exhausting resources or crashing the DMo application process.
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
iOSOperating system
<= 15.6\(1\)tCVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.0/AV:N/AC:H/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 checksWork through these to decide whether this CVE applies to you.
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Check the Cisco IOS versionUse 'show version' command and locate the firmware version string (for example, 15.6(1)T)Affected if The version number is 15.6(1)T or lower (for example, 15.5(3)T, 15.4(2)T)
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Verify if the IOx feature is enabledUse 'show iox' or 'show running-config | include iox' to see if IOx is configured and active on the deviceAffected if IOx is listed as enabled or configured in the output
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Confirm the Data in Motion (DMo) application is runningUse 'show iox service' or 'show application DMo status' to check if the DMo application process is active on the deviceAffected if DMo application is in a running or active state on the system
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Check for IOx host services configurationUse 'show running-config | include host|iox' to see if any IOx-related host services or DMo interfaces are configuredAffected if Any IOx host services or DMo-related interfaces appear in the active configuration
The device is affected if it runs Cisco iOS version 15.6(1)T or lower AND has the IOx feature enabled with DMo application active, making it vulnerable to crafted packet attacks that can crash the DMo process.
Generated from the published advisory. Verify against your own configuration.
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 dataIf the IOx feature is not required in the environment, disable it to eliminate the attack surface. Otherwise, apply Cisco's available patches for the relevant bug IDs (CSCuy82904, CSCuy82909, CSCuy82912) and implement network-level filtering to restrict untrusted traffic reaching the affected interface.
Fix this in iOS
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,600.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-6403 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2016-6403 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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