#VU49669 NULL pointer dereference in Linux kernel - CVE-2020-14356

Vulnerability identifier: #VU49669

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-14356

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a NULL pointer dereference error in the Linux kernel cgroupv2 subsystem during system reboot. A local user can crash the system or execute arbitrary code with elevated privileges.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.7 - 5.7.9

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External links
https://lists.opensuse.org/opensuse-security-announce/2020-08/msg00047.html
https://lists.opensuse.org/opensuse-security-announce/2020-09/msg00007.html
https://bugzilla.kernel.org/show_bug.cgi?id=208003
https://bugzilla.redhat.com/show_bug.cgi?id=1868453
https://lists.debian.org/debian-lts-announce/2020/09/msg00025.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html
https://lore.kernel.org/netdev/CAM_iQpUKQJrj8wE+Qa8NGR3P0L+5Uz=qo-O5+k_P60HzTde6aw%40mail.gmail.com/t/
https://security.netapp.com/advisory/ntap-20200904-0002/
https://usn.ubuntu.com/4483-1/
https://usn.ubuntu.com/4484-1/
https://usn.ubuntu.com/4526-1/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.