CVE-2026-4809
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 · uneditedplank/laravel-mediable through version 6.4.0 can allow upload of a dangerous file type when an application using the package accepts or prefers a client-supplied MIME type during file upload handling. In that configuration, a remote attacker can submit a file containing executable PHP code while declaring a benign image MIME type, resulting in arbitrary file upload.
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 confidenceThe laravel-mediable package up to v6.4.0 has a vulnerability where it accepts client-supplied MIME types during file uploads instead of validating the actual file content. An attacker can upload a PHP file containing malicious code while declaring a benign image MIME type (e.g., image/jpeg), bypassing security controls and achieving arbitrary file upload with potential remote code 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/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 checksWork through these to decide whether this CVE applies to you.
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Check the installed version of laravel-mediableLocate the laravel-mediable package in your project's vendor directory or composer.json, then run a version check command such as 'composer show plank/laravel-mediable' or inspect the version listed in your composer.lock fileAffected if The installed version is 6.4.0 or any earlier version (any version through 6.4.0)
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Determine if client-supplied MIME types are acceptedReview your application's file upload configuration files and Mediable-specific configuration (typically in config/mediable.php) to see if the 'accept_client_mime_type' or similar setting is enabled, or if the upload handler trusts the Content-Type header from the clientAffected if Client-supplied MIME types are accepted (the configuration allows the MIME type declared by the client to be used without validation)
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Verify if server-side MIME validation based on file content is implementedInspect the file upload handler or Mediable configuration to confirm whether MIME type validation uses file content or magic bytes rather than trusting the client-provided Content-Type headerAffected if No server-side validation based on actual file content is performed - the MIME type is taken directly from the client request without verification
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Identify the upload storage location and its web accessibilityCheck your application's file upload storage configuration (such as the 'disks' configuration in config/filesystems.php) and determine where uploaded files using Mediable are stored, then verify if that directory is accessible via HTTP/HTTPSAffected if Uploaded files are stored in a directory that is web-accessible (served by the web server)
You are affected if you are using laravel-mediable version 6.4.0 or earlier, your configuration accepts client-supplied MIME types without validation, and uploaded files are stored in a web-accessible directory.
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 dataConfigure the application to validate MIME types based on actual file content (magic bytes) rather than trusting client-supplied values, and restrict allowed file types to prevent executable files from being uploaded.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-4809 — 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-2026-4809 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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- 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