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Virtual File PlatformApplication · Hitachi

CVE-2021-20740

HIGH · 8.8 CVSS v3.1 Published 2021-06-28
Fix available
A fix is available. Upgrade to 5.5.3-09 / 6.4.3-09 or later.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable 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
Hitachi Virtual File Platform Versions prior to 5.5.3-09 and Versions prior to 6.4.3-09, and NEC Storage M Series NAS Gateway Nh4a/Nh8a versions prior to FOS 5.5.3-08(NEC2.5.4a) and Nh4b/Nh8b, Nh4c/Nh8c versions prior to FOS 6.4.3-08(NEC3.4.2) allow remote authenticated attackers to execute arbitrary OS commands with root privileges via unspecified vectors.

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

This is an OS command injection vulnerability in Hitachi Virtual File Platform and NEC Storage M Series NAS Gateway. The flaw allows remote authenticated attackers to execute arbitrary operating system commands with root privileges through unspecified vectors, providing complete system compromise.

MitigationUpgrade to Hitachi VFP versions 5.5.3-09 or 6.4.3-09, or NEC Storage FOS 5.5.3-08 for Nh4a/Nh8a and FOS 6.4.3-08 for Nh4b/Nh8b/Nh4c/Nh8c. Until patched, restrict administrative access to trusted users and monitor for suspicious command activity.

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
Virtual File PlatformApplication
Affected:< 6.4.3-09< 5.5.3-09
Nas Gateway Nh4a FirmwareOperating system
Affected:< fos_5.5.3-08\(nec2.5.4a\)
Nas Gateway Nh8a FirmwareOperating system
Affected:< fos_5.5.3-08\(nec2.5.4a\)
Nas Gateway Nh4b FirmwareOperating system
Affected:< fos_6.4.3-08\(nec3.4.2\)
Nas Gateway Nh8b FirmwareOperating system
Affected:< fos_6.4.3-08\(nec3.4.2\)
Nas Gateway Nh4c FirmwareOperating system
Affected:< fos_6.4.3-08\(nec3.4.2\)
Nas Gateway Nh8c FirmwareOperating system
Affected:< fos_6.4.3-08\(nec3.4.2\)

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify the installed product
    Determine whether the system runs Hitachi Virtual File Platform or one of the NEC Storage NAS Gateway models (NH4a, NH8a, NH4b, NH8b, NH4c, NH8c). Check the system documentation, web management interface, or CLI prompt for product identification.
    Affected if The product is Hitachi Virtual File Platform or NEC Storage M Series NAS Gateway
  2. Determine Hitachi VFP version
    If using Hitachi Virtual File Platform, access the management interface or run the appropriate version command (consult product documentation for version display). Compare the installed version against 5.5.3-09 and 6.4.3-09.
    Affected if Version is below 5.5.3-09 or below 6.4.3-09 (for respective major releases)
  3. Determine NEC NAS Gateway firmware version
    If using NEC NAS Gateway, check the firmware version through the management interface or CLI. Look for the FOS version string such as fos_5.5.3-08(nec2.5.4a) or fos_6.4.3-08(nec3.4.2).
    Affected if Firmware is below fos_5.5.3-08(nec2.5.4a) for NH4a/NH8a, or below fos_6.4.3-08(nec3.4.2) for NH4b/NH8b/NH4c/NH8c
  4. Assess exposure to untrusted users
    Review network access controls and authentication settings for the administrative interfaces. Determine if remote administrative access is accessible from untrusted networks.
    Affected if Administrative interfaces are accessible from untrusted or internet-facing networks with valid authenticated user accounts

A system is affected if it runs any Hitachi VFP version below 5.5.3-09 or 6.4.3-09, or any NEC NAS Gateway firmware below fos_5.5.3-08(nec2.5.4a) or fos_6.4.3-08(nec3.4.2), and allows remote authenticated access.

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 5.5.3-09 / 6.4.3-09 or later
Fixed in 5.5.3-096.4.3-09
Interim mitigation

Upgrade to Hitachi VFP versions 5.5.3-09 or 6.4.3-09, or NEC Storage FOS 5.5.3-08 for Nh4a/Nh8a and FOS 6.4.3-08 for Nh4b/Nh8b/Nh4c/Nh8c. Until patched, restrict administrative access to trusted users and monitor for suspicious command activity.

Recommended fix High confidence

Hitachi Virtual File Platform: 5.5.3-09 or 6.4.3-09; NEC NAS Gateway Nh4a/Nh8a: FOS 5.5.3-08(NEC2.5.4a); NEC NAS Gateway Nh4b/Nh8b/Nh4c/Nh8c: FOS 6.4.3-08(NEC3.4.2)

  1. 1. Identify the currently installed Hitachi Virtual File Platform or NEC Storage M Series NAS Gateway version and model.
  2. 2. For Hitachi Virtual File Platform: If running version 5.x, upgrade to version 5.5.3-09 or later. If running version 6.x, upgrade to version 6.4.3-09 or later.
  3. 3. For NEC Storage M Series NAS Gateway Nh4a/Nh8a: Upgrade to FOS 5.5.3-08(NEC2.5.4a) or later.
  4. 4. For NEC Storage M Series NAS Gateway Nh4b/Nh8b/Nh4c/Nh8c: Upgrade to FOS 6.4.3-08(NEC3.4.2) or later.
  5. 5. Obtain the firmware/upgrade package from the official vendor support portal (jpn.nec.com or Hitachi support).
  6. 6. Follow the vendor's documented upgrade procedure for your specific model, ensuring proper backup of configuration data.
  7. 7. After upgrade, verify the system is functioning correctly and confirm the version number has been updated.
Caveat Standard firmware upgrade risks apply - ensure configuration backup before upgrading and plan for potential downtime

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

Fix this in Virtual File Platform 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
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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-2021-20740 in production — separate from our analysis above.

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What belongs here
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