Intel

AIKIDO-2026-155029

league/flysystem is vulnerable to Improper Input Validation

Improper Input ValidationGHSA-cxf4-7mrp-vvpr Published 2 days ago

43

Medium Risk

This Affects:

PHPleague/flysystem
0.1.0 - 3.35.2
Fixed in 3.35.3
Are you affected? Scan for Free

TL;DR

The WhitespacePathNormalizer class validates paths by scanning for control characters with a preg_match call that uses the Unicode modifier. When a path contains malformed UTF-8, preg_match returns false instead of a match count, and the truthy check treats that failure as a clean path so CorruptedPathDetected is never thrown. Because this normalizer is the default across the Local, FTP, SFTP, S3, and other adapters, file names carrying invalid UTF-8 bytes together with embedded terminal escape or control sequences pass validation and are stored. The fix compares the preg_match result against zero so both malformed UTF-8 and real matches are rejected as corrupted paths.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range and you store or list file names derived from untrusted input.

Background info

league/flysystem is vulnerable to Improper Input Validation in versions 0.1.0 - 3.35.2.

How to fix this

Upgrade the league/flysystem library to the patch version.

Are You Affected?

Connect your repositories to instantly see whether vulnerable or malicious packages exist in your codebase.

Free. No credit card required.

Aikido Platform