Nx OsOperating system · Cisco
CVE-2018-0302
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 · uneditedA vulnerability in the CLI parser of Cisco FXOS Software and Cisco UCS Fabric Interconnect Software could allow an authenticated, local attacker to cause a buffer overflow on an affected device. The vulnerability is due to incorrect input validation in the CLI parser subsystem. An attacker could exploit this vulnerability by exceeding the expected length of user input. A successful exploit could allow the attacker to execute arbitrary code with root privileges on the affected system. This vulnerability affects Firepower 4100 Series Next-Generation Firewall, Firepower 9300 Security Appliance, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvb61099, CSCvb86743.
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 confidenceBuffer overflow vulnerability in the CLI parser of Cisco FXOS Software and Cisco UCS Fabric Interconnect Software allows authenticated local attackers to exceed expected input length, potentially executing arbitrary code with root privileges.
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
Nx OsOperating system
= 3.1\(1k\)a
Firepower Extensible Operating SystemOperating system
>= 1.1, < 1.1.4.169>= 2.0, < 2.0.1.135CVSS 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
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify the FXOS or NX-OS versionLog into the device and run 'show version' or 'fxos version' command to retrieve the installed software versionAffected if The version matches the affected ranges: FXOS 1.1.x < 1.1.4.169, FXOS 2.0.x < 2.0.1.135, or NX-OS exactly 3.1(1k)a on UCS Fabric Interconnect
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Confirm the hardware platform is FXOS-based or UCS Fabric InterconnectRun 'show inventory' or 'show chassis hardware' to identify the platform typeAffected if The device is a Cisco Firepower 4100/9300 series (FXOS) or Cisco UCS 6200/6300 series Fabric Interconnect running the affected NX-OS version 3.1(1k)a
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Verify local CLI authentication is configuredCheck the configuration with 'show running-config | include username' or review AAA settings to confirm local CLI accounts existAffected if Local CLI authentication is enabled and user accounts are present, allowing authenticated access to the CLI parser where the buffer overflow occurs
The environment is affected if the device runs Cisco FXOS versions 1.1.x before 1.1.4.169 or 2.0.x before 2.0.1.135, or Cisco NX-OS version 3.1(1k)a on UCS Fabric Interconnect, and local CLI access with valid credentials is available.
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 data1.1.4.1692.0.1.135
Apply Cisco-provided software updates for affected FXOS and UCS Fabric Interconnect versions. Restrict local CLI access to trusted personnel only until patches are deployed.
Fix this in Nx Os
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 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 $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-0302 — 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-2018-0302 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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