dbcve.org
Nx OsOperating system · Cisco

CVE-2018-0301

CRITICAL · 9.8 CVSS v3.0 Published 2018-06-20
Fix available
A fix is available. Upgrade to 7.0 / 7.3 or later.
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
A vulnerability in the NX-API feature of Cisco NX-OS Software could allow an unauthenticated, remote attacker to craft a packet to the management interface on an affected system, causing a buffer overflow. The vulnerability is due to incorrect input validation in the authentication module of the NX-API subsystem. An attacker could exploit this vulnerability by sending a crafted HTTP or HTTPS packet to the management interface of an affected system with the NX-API feature enabled. An exploit could allow the attacker to execute arbitrary code as root. Note: NX-API is disabled by default. This vulnerability affects: MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules. Cisco Bug IDs: CSCvd45804, CSCve02322, CSCve02412.

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

A buffer overflow vulnerability in the NX-API feature of Cisco NX-OS Software exists due to incorrect input validation in the authentication module. An unauthenticated remote attacker can send crafted HTTP/HTTPS packets to the management interface of affected systems with NX-API enabled, potentially executing arbitrary code with root privileges.

MitigationEnsure NX-API remains disabled (default state) until the appropriate Cisco firmware update is applied. If NX-API is required, upgrade to a patched version and restrict management interface access to trusted networks.

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
Affected:>= 6.0, < 7.3\(3\)n1\(1\)>= 7.2, < 7.3\(2\)d1\(1\)>= 8.0, < 8.1\(1\)= 8.1= 8.2< 7.0\(3\)i4>= 7.0\(3\)i5, < 7.0\(3\)i7\(1\)= 7.0\(3\)i7>= 7.3, < 7.3\(3\)n1\(1\)= 6.0= 7.0= 7.1

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. Verify NX-API is enabled
    Run the command 'show nxapi' or 'show feature | include nxapi' on the Cisco NX-OS device to check if the NX-API feature is enabled
    Affected if NX-API status shows as 'enabled' - the vulnerability only affects systems with NX-API turned on
  2. Check NX-OS version
    Run the command 'show version' on the Cisco NX-OS device to obtain the installed software version
    Affected if The version falls within the affected ranges: 6.0, 7.0, 7.1, 7.0(3)i4, 7.0(3)i5 through 7.0(3)i7(1), 7.2 through 7.3(2)d1(1), 7.3 through 7.3(3)n1(1), 8.0 through 8.1(1), or 8.2
  3. Confirm management interface access
    Review the NX-API configuration by running 'show run nxapi' to see if the management interface is configured for NX-API access
    Affected if NX-API is bound to the management interface (typically eth0 or mgmt0) and is reachable from untrusted networks

A system is affected if NX-API is enabled AND the NX-OS version matches one of the listed vulnerable versions, regardless of management interface network exposure since the attack targets the management interface.

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.

dbcve · scoped
Upgrade available Upgrade to 7.0 / 7.3 / 8.1 or later
Fixed in 7.07.38.1
Interim mitigation

Ensure NX-API remains disabled (default state) until the appropriate Cisco firmware update is applied. If NX-API is required, upgrade to a patched version and restrict management interface access to trusted networks.

Recommended fix High confidence

NX-OS 7.3(3)n1(1) or later for n1 platforms; 7.3(2)d1(1) or later for d1 platforms; 8.1(1) or later (preferably latest 8.x stable)

  1. 1. Verify NX-API is currently enabled on the affected system using the 'show nx-api' command.
  2. 2. If NX-API is enabled and not needed, disable it using 'no nx-api' in configuration mode to eliminate the attack surface as an immediate mitigation.
  3. 3. Identify the current NX-OS version using 'show version' command.
  4. 4. Determine the appropriate upgrade path based on current version branch (6.x, 7.x, or 8.x).
  5. 5. Download the fixed NX-OS image from Cisco (see tools.cisco.com for your specific hardware model).
  6. 6. For version 6.0 to 7.2: Upgrade to NX-OS 7.3(3)n1(1) or later for n1 platform, or 7.3(2)d1(1) or later for d1 platform.
  7. 7. For version 7.2 to 7.3: Upgrade to NX-OS 7.3(3)n1(1) or later, or 7.3(2)d1(1) or later.
  8. 8. For version 8.0.x: Upgrade to NX-OS 8.1(1) or later, preferably the latest 8.x stable release.
Caveat Review Cisco release notes for your specific hardware platform for any migration considerations; some hardware may require specific NX-OS train support

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Nx Os Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA2.0 h
20.0 hours of engineering $3,500
Get the upgrade done

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 locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-0301 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2018-0301 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