Bug 2369407 (CVE-2025-40909)

Summary:	CVE-2025-40909 perl: Perl threads have a working directory race condition where file operations may target unintended paths
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	adudiak, crizzo, dfreiber, drow, jburrell, jmitchel, jtanner, kshier, omaciel, stcannon, vkumar, yguenane
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in the Perl standard library threads component. This vulnerability can allow a local attacker to exploit a race condition in directory handling to access files or load code from unexpected locations.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2369462, 2369463
Bug Blocks:

Description OSIDB Bzimport 2025-05-30 13:01:12 UTC

Perl threads have a working directory race condition where file operations may target unintended paths.

If a directory handle is open at thread creation, the process-wide current working directory is temporarily changed in order to clone that handle for the new thread, which is visible from any third (or more) thread already running. 

This may lead to unintended operations such as loading code or accessing files from unexpected locations, which a local attacker may be able to exploit.

The bug was introduced in commit 11a11ecf4bea72b17d250cfb43c897be1341861e and released in Perl version 5.13.6