SB2020042448 - Type confusion in Linux kernel
Published: April 24, 2020
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) Type confusion (CVE-ID: CVE-2019-15792)
The vulnerability allows a local user to execute arbitrary code.
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() calls fdget(oldfd), then without further checks passes the resulting file* into shiftfs_real_fdget(), which casts file->private_data, a void* that points to a filesystem-dependent type, to a 'struct shiftfs_file_info *'. As the private_data is not required to be a pointer, an attacker can use this to cause a denial of service or possibly execute arbitrary code.
Remediation
Install update from vendor's website.