Flysystem is an open source file storage library for PHP. The whitespace normalisation using in 1.x and 2.x removes any unicode whitespace. Under certain specific conditions this could potentially allow a malicious user to execute code remotely. The conditions are: A user is allowed to supply the path or filename of an uploaded file, the supplied path or filename is not checked against unicode chars, the supplied pathname checked against an extension deny-list, not an allow-list, the supplied path or filename contains a unicode whitespace char in the extension, the uploaded file is stored in a directory that allows PHP code to be executed. Given these conditions are met a user can upload and execute arbitrary code on the system under attack. The unicode whitespace removal has been replaced with a rejection (exception). For 1.x users, upgrade to 1.1.4. For 2.x users, upgrade to 2.1.1.
CVE-2021-32708 - High Severity Vulnerability
Filesystem abstraction: Many filesystems, one API.
Library home page: https://api.github.com/repos/thephpleague/flysystem/zipball/0e9db7f0b96b9f12dcf6f65bc34b72b1a30ea55a
Dependency Hierarchy: - tightenco/ziggy-v0.7.1 (Root Library) - laravel/framework-v5.5.48 - :x: **league/flysystem-1.0.57** (Vulnerable Library)
Found in HEAD commit: 6937a6413a72bc7060c19b8195035c2b9504cbd2
Found in base branch: master
Flysystem is an open source file storage library for PHP. The whitespace normalisation using in 1.x and 2.x removes any unicode whitespace. Under certain specific conditions this could potentially allow a malicious user to execute code remotely. The conditions are: A user is allowed to supply the path or filename of an uploaded file, the supplied path or filename is not checked against unicode chars, the supplied pathname checked against an extension deny-list, not an allow-list, the supplied path or filename contains a unicode whitespace char in the extension, the uploaded file is stored in a directory that allows PHP code to be executed. Given these conditions are met a user can upload and execute arbitrary code on the system under attack. The unicode whitespace removal has been replaced with a rejection (exception). For 1.x users, upgrade to 1.1.4. For 2.x users, upgrade to 2.1.1.
Publish Date: 2021-06-24
URL: CVE-2021-32708
Base Score Metrics: - Exploitability Metrics: - Attack Vector: Network - Attack Complexity: High - Privileges Required: None - User Interaction: None - Scope: Unchanged - Impact Metrics: - Confidentiality Impact: High - Integrity Impact: High - Availability Impact: High
For more information on CVSS3 Scores, click here.Type: Upgrade version
Origin: https://github.com/thephpleague/flysystem/security/advisories/GHSA-9f46-5r25-5wfm
Release Date: 2021-06-24
Fix Resolution: 1.1.4,2.1.1