Perl: Race condition vulnerability

Background

File::Path module provides a convenient way to create directories of arbitrary depth and to delete an entire directory subtree from the filesystem.

Description

A race condition occurs within concurrent environments. This condition was discovered by The cPanel Security Team in the rmtree and remove_tree functions in the File-Path module before 2.13 for Perl. This is due to the time-of-check-to-time-of-use (TOCTOU) race condition between the stat() that decides the inode is a directory and the chmod() that tries to make it user-rwx.

Impact

A local attacker could exploit this condition to set arbitrary mode values on arbitrary files and hence bypass security restrictions.

Workaround

There is no known workaround at this time.

Resolution

All Perl users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=dev-lang/perl-5.24.1-r2"

All File-Path users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=perl-core/File-Path-2.130.0"

All Perl-File-Path users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=virtual/perl-File-Path-2.130.0"