#VU90393 NULL pointer dereference in Linux kernel - CVE-2021-47526

Vulnerability identifier: #VU90393

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47526

CWE-ID: CWE-476

Exploitation vector: Local

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to NULL pointer dereference within the liteuart_probe() function in drivers/tty/serial/liteuart.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.15, 5.15 rc1, 5.15 rc2, 5.15 rc3, 5.15 rc4, 5.15 rc5, 5.15 rc6, 5.15 rc7, 5.15.0, 5.15.1, 5.15.2, 5.15.3, 5.15.4, 5.15.5, 5.15.6, 5.16 rc1, 5.16 rc2, 5.16 rc3, 5.16 rc4, 5.16 rc5, 5.16 rc6, 5.16 rc8

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External links
https://git.kernel.org/stable/c/189c99c629bbf85916c02c153f904649cc0a9d7f
https://git.kernel.org/stable/c/0f55f89d98c8b3e12b4f55f71c127a173e29557c
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.7
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16

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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.