The aufs module for the Linux kernel 3.x and 4.x does not properly restrict the mount namespace, which allows local users to gain privileges by mounting an aufs filesystem on top of a FUSE filesystem, and then executing a crafted setuid program.
https://sourceforge.net/p/aufs/mailman/message/34864744/
http://www.openwall.com/lists/oss-security/2021/10/18/1
https://euvd.enisa.europa.eu/vulnerability/EUVD-2016-3926
http://www.securityfocus.com/bid/96839
http://www.openwall.com/lists/oss-security/2016/02/24/9
http://www.halfdog.net/Security/2016/AufsPrivilegeEscalationInUserNamespaces/
Source: Mitre, NVD
Published: 2016-05-02
Updated: 2026-06-17
Base Score: 4.4
Vector: CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P
Severity: Medium
Base Score: 7.8
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity: High
EPSS: 0.00905