#VU34985 Use-after-free in Linux kernel - CVE-2019-19447

Vulnerability identifier: #VU34985

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2019-19447

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

In the Linux kernel 5.0.21, mounting a crafted ext4 filesystem image, performing some operations, and unmounting can lead to a use-after-free in ext4_put_super in fs/ext4/super.c, related to dump_orphan_list in fs/ext4/super.c.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.0.21

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External links
https://lists.opensuse.org/opensuse-security-announce/2020-03/msg00021.html
https://github.com/bobfuzzer/CVE/tree/master/CVE-2019-19447
https://lists.debian.org/debian-lts-announce/2020/03/msg00001.html
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-20200103-0001/

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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.