Unrestricted File UploadWeakness · CWE-434

CVE-2025-23918

CRITICAL · 9.9 CVSS v3.1 Published 2025-01-22
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 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
Unrestricted Upload of File with Dangerous Type vulnerability in Enrico Sandoli Smallerik File Browser smallerik-file-browser allows Upload a Web Shell to a Web Server.This issue affects Smallerik File Browser: from n/a through <= 1.1.

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

The Smallerik File Browser application suffers from an unrestricted file upload vulnerability that allows attackers to upload malicious web shell scripts to the web server. Due to insufficient validation of uploaded file types, an attacker can bypass restrictions and upload executable scripts (e.g., PHP, JSP, ASP) that can then be accessed via HTTP to achieve remote code execution.

MitigationImplement strict allowlist-based file validation checking both file extension AND content-type/magic bytes, store uploads outside webroot or disable script execution in the upload directory, and rename uploaded files to prevent direct execution.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

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
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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 Smallerik File Browser installation
    Search for Smallerik File Browser in your installed applications, web server document roots, or running services. Check for directories named 'filebrowser', 'smallerik', or similar. Review your web server config for any file browser applications.
    Affected if Smallerik File Browser is present in the environment
  2. Determine the installed version
    Check the application's about page, README, or configuration files for version information. Look in the application root directory for version markers.
    Affected if Version cannot be determined or is unknown (assume affected)
  3. Verify if file upload feature is enabled
    Access the file browser interface and attempt to locate an upload function. Check application configuration files for upload-related settings (e.g., enable_upload, allow_upload).
    Affected if File upload functionality is accessible to users
  4. Test file type validation
    Attempt to upload a test file with executable extensions such as .php, .jsp, .asp, or .exe through the file browser upload interface. Observe whether the upload succeeds or is rejected.
    Affected if Executable file extensions are accepted and stored on the server
  5. Check upload storage location
    Examine application configuration or inspect where uploaded files are stored. Determine if the upload directory is within the web server's document root (webroot) or outside it.
    Affected if Uploaded files are stored within the webroot and accessible via HTTP

If Smallerik File Browser is installed with file upload enabled and accepts executable script extensions (PHP, JSP, ASP) that are stored in a web-accessible location, the environment is vulnerable to CVE-2025-23918.

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

Implement strict allowlist-based file validation checking both file extension AND content-type/magic bytes, store uploads outside webroot or disable script execution in the upload directory, and rename uploaded files to prevent direct execution.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA3.0 h
19.0 hours of engineering $3,380
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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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-2025-23918 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
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