Unsafe Client MIME Type Handling Can Enable Arbitrary File Upload in plank/laravel-mediable (CVE-2026-4809) | HOL Guard CVE

Critical · CVSS 9.8CVE-2026-4809

Unsafe Client MIME Type Handling Can Enable Arbitrary File Upload in plank/laravel-mediable

Answer in brief

CVE-2026-4809 records a Critical severity (CVSS 9.8) vulnerability in Unsafe Client MIME Type Handling Can Enable Arbitrary File Upload in plank/laravel-mediable. The current sources do not mark it as known exploited. The current feed maps plank/laravel-mediable (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Mar 26, 2026Updated Aug 10, 2026Source checked Sep 24, 2026First seen by HOL Aug 10, 2026Material review Aug 10, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.8
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps plank/laravel-mediable (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
plank/laravel-mediablegeneric	<= 6.4.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for plank/laravel-mediable.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Mar 26, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 10, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 10, 2026

Sources and claim methodology

Upstream source description

plank/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.

Quoted source text, attributed separately from HOL analysis.