Bug 1975956 (CVE-2021-32708)

Summary:	CVE-2021-32708 php-league-flysystem: Time-of-check Time-of-use Race Condition
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED UPSTREAM	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	fedora, shawn
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-06-24 22:40:25 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1975957, 1975958
Bug Blocks:

Description Guilherme de Almeida Suckevicz 2021-06-24 19:57:07 UTC

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.

Reference:
https://github.com/thephpleague/flysystem/security/advisories/GHSA-9f46-5r25-5wfm

Comment 1 Guilherme de Almeida Suckevicz 2021-06-24 19:57:26 UTC

Created php-league-flysystem tracking bugs for this issue:

Affects: epel-7 [bug 1975958]
Affects: fedora-all [bug 1975957]

Comment 2 Product Security DevOps Team 2021-06-24 22:40:25 UTC

This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.