Use-after-free in Linux kernel - CVE-2020-10690
Published: May 8, 2020 / Updated: July 17, 2020
Vulnerability identifier: #VU30292
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-10690
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
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
Install update from vendor's website.
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/