#VU30584 NULL pointer dereference in Linux kernel - CVE-2019-19227


| Updated: 2020-07-17

Vulnerability identifier: #VU30584

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-2019-19227

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 remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the AppleTalk subsystem in the Linux kernel before 5.1, there is a potential NULL pointer dereference because register_snap_client may return NULL. This will lead to denial of service in net/appletalk/aarp.c and net/appletalk/ddp.c, as demonstrated by unregister_snap_client, aka CID-9804501fa122. A remote attacker can perform a denial of service (DoS) attack.

Mitigation
Update to version 5.1.

Vulnerable software versions

Linux kernel: 5.0 - 5.0.21


External links
https://lists.opensuse.org/opensuse-security-announce/2019-12/msg00029.html
https://packetstormsecurity.com/files/155890/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.1
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9804501fa1228048857910a6bf23e085aade37cc
https://lists.debian.org/debian-lts-announce/2020/01/msg00013.html
https://lists.debian.org/debian-lts-announce/2020/03/msg00001.html
https://seclists.org/bugtraq/2020/Jan/10
https://security.netapp.com/advisory/ntap-20200103-0001/
https://usn.ubuntu.com/4254-1/
https://usn.ubuntu.com/4254-2/
https://usn.ubuntu.com/4258-1/
https://usn.ubuntu.com/4287-1/
https://usn.ubuntu.com/4287-2/


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.


Latest bulletins with this vulnerability