CVE-2015-8953
kernel: overlayfs: Double dentry reference leak in copy-up failure
Severity
ModerateRed Hat Product Security
CVSS 3.0
Review impact separately from score.
Published · August 23, 2016
Updated · November 21, 2025
Description
A flaw was found in the Linux kernel's implementation of overlayfs. An attacker can leak file resources in the system by opening a large file with write permissions on a overlay filesystem that is insufficient to deal with the size of the write.
When unmounting the underlying device, the system is unable to free an inode and this will consume resources. Repeating this for all available inodes and memory will create a denial of service situation.
Statement
This issue does not affect the Linux kernel packages as shipped with Red Hat Enterprise Linux 5, 6 as the code with the flaw is not present in the products listed.
This issue affects the Linux kernel packages as shipped with Red Hat Enterprise Linux 7 and MRG-2. This has been rated as having Moderate security impact and is not currently planned to be addressed in future updates. For additional information, refer to the Red Hat Enterprise Linux Life Cycle: https://access.redhat.com/support/policy/updates/errata/.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.0 · 6.1CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
CVSS 2.0 · 5.4AV:L/AC:M/Au:N/C:P/I:N/A:C
CWE-772 · Missing Release of Resource after Effective Lifetime