NULL pointer dereference in Linux kernel x86 hyperv

1) NULL pointer dereference

EUVDB-ID: #VU90584

Risk: Low

CVSSv3.1: 4.8 [AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-47217

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

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 set_hv_tscchange_cb() function in arch/x86/hyperv/hv_init.c. A local user can perform a denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

External links

http://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743
http://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661
http://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c
http://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8
http://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4

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.