In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image, performing some operations, and then making a syncfs system call can lead to a use-after-free in __mutex_lock in kernel/locking/mutex.c. This is related to mutex_can_spin_on_owner in kernel/locking/mutex.c, __btrfs_qgroup_free_meta in fs/btrfs/qgroup.c, and btrfs_insert_delayed_items in fs/btrfs/delayed-inode.c.
https://github.com/bobfuzzer/CVE/tree/master/CVE-2019-19813
https://lists.debian.org/debian-lts-announce/2020/09/msg00025.html
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
Source: MITRE
Published: 2019-12-17
Updated: 2021-03-12
Type: CWE-416
Base Score: 7.1
Vector: AV:N/AC:M/Au:N/C:N/I:N/A:C
Impact Score: 6.9
Exploitability Score: 8.6
Severity: HIGH
Base Score: 5.5
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Impact Score: 3.6
Exploitability Score: 1.8
Severity: MEDIUM