#VU28405 NULL pointer dereference in Linux kernel - CVE-2019-19037

Vulnerability identifier: #VU28405

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-2019-19037

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 fs/ext4/namei.c in the Linux kernel through 5.3.12 allows a NULL pointer dereference because ext4_read_dirblock(inode,0,DIRENT_HTREE) can be zero. A remote attacker can perform a denial of service (DoS) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Linux kernel: 4.9 - 4.9.207, 4.14 - 4.19.91, 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

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External links
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.161
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.92
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.7
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.208
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.5

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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.