NULL pointer dereference in Linux kernel

1) NULL pointer dereference

EUVDB-ID: #VU28405

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 - NULL Pointer Dereference

Exploit availability: No

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 - 5.4.42

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:4.9.207:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:4.19.91:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.0.21:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.1.21:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.2.21:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.3.18:*:*:*:*:*:*:*
• cpe:2.3:o:linux_foundation:linux_kernel:5.4.42:*:*:*:*:*:*:*

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

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.