GlusterFS does not properly sanitize file paths in the "trusted.io-stats-dump" extended attribute (xattr) as used by the "debug/io-stats" translator. The value of this extended attribute is not properly sanitized and can be exploited by an attacker to create files in arbitrary locations and subsequently execute arbitrary code. To exploit this an attacker would require sufficient access to modify the extended attributes of files on a Gluster volume.
Acknowledgments: Name: Michael Hanselmann (hansmi.ch)
Statement: This issue did not affect Red Hat Enterprise Linux 6 and 7 as the flaw is present in glusterfs-server, which is not shipped there. This flaw affects glusterfs versions included in Red Hat Virtualization 4 Hypervisor. However, in recommended configurations, the vulnerability is only exposed to hypervisor administrators and can not be exploited from virtual machines or other hosts on the network. For Red Hat Virtualization, Product Security has rated this flaw as Moderate. For additional information, refer to the Issue Severity Classification: https://access.redhat.com/security/updates/classification/.
This issue has been addressed in the following products: Red Hat Gluster Storage 3.4 for RHEL 7 Native Client for RHEL 7 for Red Hat Storage Via RHSA-2018:2607 https://access.redhat.com/errata/RHSA-2018:2607
This issue has been addressed in the following products: Red Hat Gluster Storage 3.4 for RHEL 6 Native Client for RHEL 6 for Red Hat Storage Via RHSA-2018:2608 https://access.redhat.com/errata/RHSA-2018:2608
Created glusterfs tracking bugs for this issue: Affects: fedora-all [bug 1625103]
upstream fix: https://review.gluster.org/21072
Mitigation: To limit exposure of gluster server nodes : 1. gluster server should be on LAN and not reachable from public networks. 2. Use gluster auth.allow and auth.reject. 3. Use TLS certificates to authenticate gluster clients. caveat: This does not protect from attacks against authenticated gluster clients.
This issue has been addressed in the following products: Red Hat Virtualization 4 for Red Hat Enterprise Linux 7 Via RHSA-2018:3470 https://access.redhat.com/errata/RHSA-2018:3470