CVE-2019-15791: Reference count underflow in shiftfs
In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfsbtrfsioctlfdreplace() installs an fd referencing a file from the lower filesystem without taking an additional reference to that file. After the btrfs ioctl completes this fd is closed, which then puts a reference to that file, leading to a refcount underflow.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.187-1Fixed in 6.12.107-1Fixed in 7.1.13-1
Event History
Frequently Asked Questions
What is CVE-2019-15791?
CVE-2019-15791 is a vulnerability in shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series.
Which software versions are affected by CVE-2019-15791?
CVE-2019-15791 affects Ubuntu Linux versions 2.6.12~ up to, but not including, 5.3.0-22.24.
How can I fix the CVE-2019-15791 vulnerability?
To fix the CVE-2019-15791 vulnerability, update your Ubuntu Linux kernel to version 5.3.0-22.24 or higher.
Are there any references for CVE-2019-15791?
Yes, you can find references for CVE-2019-15791 at the following links: [Reference 1](https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=601a64857b3d7040ca15c39c929e6b9db3373ec1), [Reference 2](https://usn.ubuntu.com/usn/usn-4183-1), [Reference 3](https://usn.ubuntu.com/usn/usn-4184-1).