Use-after-free in Linux kernel - CVE-2020-10690
Published: May 8, 2020 / Updated: July 17, 2020
Linux kernel
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux Workstation
Slackware Linux
Ubuntu
Oracle VM Server for x86
kernel (Red Hat package)
kernel-rt (Red Hat package)
linux-image-generic-lts-xenial (Ubuntu package)
linux-image-generic-lpae-lts-xenial (Ubuntu package)
linux-image-lowlatency-lts-xenial (Ubuntu package)
linux-image-powerpc-e500mc-lts-xenial (Ubuntu package)
linux-image-powerpc-smp-lts-xenial (Ubuntu package)
linux-image-powerpc64-emb-lts-xenial (Ubuntu package)
linux-image-powerpc64-smp-lts-xenial (Ubuntu package)
linux-image-virtual-lts-xenial (Ubuntu package)
linux-image-lowlatency (Ubuntu package)
linux-image-virtual (Ubuntu package)
linux-image-powerpc64-smp (Ubuntu package)
linux-image-powerpc64-emb (Ubuntu package)
linux-image-powerpc-smp (Ubuntu package)
linux-image-powerpc-e500mc (Ubuntu package)
linux-image-generic-lpae (Ubuntu package)
linux-image-generic (Ubuntu package)
linux-image-4.4.0-185-generic (Ubuntu package)
linux-image-4.4.0-185-powerpc64-smp (Ubuntu package)
linux-image-4.4.0-185-generic-lpae (Ubuntu package)
linux-image-4.4.0-185-powerpc64-emb (Ubuntu package)
linux-image-4.4.0-185-powerpc-smp (Ubuntu package)
linux-image-4.4.0-185-lowlatency (Ubuntu package)
linux-image-4.4.0-185-powerpc-e500mc (Ubuntu package)
linux-image-aws (Ubuntu package)
linux-image-4.4.0-1074-aws (Ubuntu package)
linux-image-kvm (Ubuntu package)
linux-image-4.4.0-1076-kvm (Ubuntu package)
linux-image-4.4.0-1110-aws (Ubuntu package)
linux-image-raspi2 (Ubuntu package)
linux-image-4.4.0-1135-raspi2 (Ubuntu package)
linux-image-snapdragon (Ubuntu package)
linux-image-4.4.0-1139-snapdragon (Ubuntu package)
linux-4.4.227/kernel-generic
linux-4.4.227/kernel-huge
linux-4.4.227/kernel-modules
linux-4.4.227/kernel-headers
Detailed vulnerability description
The vulnerability allows a local privileged user to execute arbitrary code.
There is a use-after-free in kernel versions before 5.5 due to a race condition between the release of ptp_clock and cdev while resource deallocation. When a (high privileged) process allocates a ptp device file (like /dev/ptpX) and voluntarily goes to sleep. During this time if the underlying device is removed, it can cause an exploitable condition as the process wakes up to terminate and clean all attached files. The system crashes due to the cdev structure being invalid (as already freed) which is pointed to by the inode.
How to mitigate CVE-2020-10690
Sources
- http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00022.html
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-10690
- https://lists.debian.org/debian-lts-announce/2020/06/msg00011.html
- https://lists.debian.org/debian-lts-announce/2020/06/msg00013.html
- https://security.netapp.com/advisory/ntap-20200608-0001/