Vulnerability identifier: #VU28418

Vulnerability risk: Low

CVSSv3.1: 6.4 [CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-19377

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 non-authenticated attacker to execute arbitrary code.

In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image, performing some operations, and unmounting can lead to a use-after-free in btrfs_queue_work in fs/btrfs/async-thread.c.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.4 - 5.4.32, 5.5 - 5.5.17, 5.6 - 5.6.4

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External links
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.33
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.5.18
http://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.5

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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.