#VU30292 Use-after-free in Linux kernel - CVE-2020-10690
Vulnerability identifier: #VU30292
Vulnerability risk: Low
CVSSv4.0: 4 [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
Exploit availability: No
Vulnerable software:
Linux kernel
Operating systems & Components /
Operating system
Vendor: Linux Foundation
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.
Mitigation
Install update from vendor's website.
Vulnerable software versions
Linux kernel: 5.0 - 5.0.21, 5.1 rc1 - 5.1.21, 5.2 - 5.2.21, 5.3 - 5.3.18, 5.4 - 5.4.42
External links
https://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/
Q & A
Can this vulnerability be exploited remotely?
No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.
Is there known malware, which exploits this vulnerability?
No. We are not aware of malware exploiting this vulnerability.
