cbcvebase.
CVE-2019-15791
published 2020-04-24

CVE-2019-15791: In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfs_btrfs_ioctl_fd_replace() installs an fd…

PriorityP342high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EXPLOIT
EPSS
1.32%
67.2th percentile
In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfs_btrfs_ioctl_fd_replace() 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

7 ranges
VendorProductVersion rangeFixed in
canonicalubuntu_linux
canonicalubuntu_linux
debianlinux
linuxlinux_kernel
linuxlinux_kernel
ubuntushiftfs_in_the_linux_kernel>= 5.0 kernel < 5.0.0-35.385.0.0-35.38
ubuntushiftfs_in_the_linux_kernel>= 5.3.0-11.12 < 5.3 kernel*5.3 kernel*

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.04.6MEDIUMAV:L/AC:L/Au:N/C:P/I:P/A:P
osv7.8HIGH
vendor_debian7.1LOW
vendor_redhat7.1HIGH
vendor_ubuntu6.5MEDIUM
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