File ManagerApplication · Elecom

CVE-2021-20651

CRITICAL · 9.1 CVSS v3.1 Published 2021-02-12
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
Directory traversal vulnerability in ELECOM File Manager all versions allows remote attackers to create an arbitrary file or overwrite an existing file in a directory which can be accessed with the application 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 · moderate confidence

Directory traversal vulnerability in ELECOM File Manager allows remote attackers to manipulate file paths using traversal sequences (e.g., '../') to write arbitrary files or overwrite existing files in directories accessible by the application's privileges, potentially enabling remote code execution or complete system compromise.

MitigationApply vendor patch if available; otherwise, implement strict input validation on all file path parameters to reject directory traversal sequences and enforce allowlist-based path validation.

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
File ManagerApplication
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
None
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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 if ELECOM File Manager is installed
    Check system for ELECOM File Manager installation - look for application binaries, services, or processes named 'Elecom', 'ELECOM', or 'File Manager' in installed programs, running processes, or system services
    Affected if ELECOM File Manager software is found running or installed on the system
  2. Verify the file transfer or upload feature is enabled
    Check application configuration or service settings for file transfer, upload, or file sharing functionality - look for features that accept file paths or allow file operations
    Affected if File transfer, upload, or file sharing feature is enabled and accessible
  3. Check if the application service is network-accessible
    Inspect network listening services on the host - check ports or services associated with ELECOM File Manager to determine if remote connections are possible
    Affected if The application service is exposed to network access (localhost or remote)
  4. Confirm affected version range
    Retrieve installed version through application executable properties, installed programs list, or running service information, then confirm it falls within 'all versions' (which includes any version of ELECOM File Manager)
    Affected if Any version of ELECOM File Manager is installed (since all versions are affected)

If ELECOM File Manager is installed with file transfer/upload capabilities enabled and accessible, the system is vulnerable to directory traversal attacks that could allow remote attackers to write or overwrite arbitrary files.

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

Apply vendor patch if available; otherwise, implement strict input validation on all file path parameters to reject directory traversal sequences and enforce allowlist-based path validation.

Fix this in File Manager Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,176.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-20651 — 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 sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-20651 in production — separate from our analysis above.

No notes yet

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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