#VU90584 NULL pointer dereference in Linux kernel - CVE-2021-47217
Vulnerability identifier: #VU90584
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:
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 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: 4.19, 4.19.1, 4.19.2, 4.19.3, 4.19.4, 4.19.5, 4.19.6, 4.19.7, 4.19.8, 4.19.9, 4.19.10, 4.19.11, 4.19.12, 4.19.13, 4.19.14, 4.19.15, 4.19.16, 4.19.17, 4.19.18, 4.19.19, 4.19.20, 4.19.21, 4.19.22, 4.19.23, 4.19.24, 4.19.25, 4.19.26, 4.19.27, 4.19.28, 4.19.29, 4.19.30, 4.19.31, 4.19.32, 4.19.33, 4.19.34, 4.19.35, 4.19.36, 4.19.37, 4.19.38, 4.19.39, 4.19.40, 4.19.41, 4.19.42, 4.19.43, 4.19.44, 4.19.45, 4.19.46, 4.19.47, 4.19.48, 4.19.49, 4.19.50, 4.19.51, 4.19.52, 4.19.53, 4.19.54, 4.19.55, 4.19.56, 4.19.57, 4.19.58, 4.19.59, 4.19.60, 4.19.61, 4.19.62, 4.19.63, 4.19.64, 4.19.65, 4.19.66, 4.19.67, 4.19.68, 4.19.69, 4.19.70, 4.19.71, 4.19.72, 4.19.73, 4.19.74, 4.19.75, 4.19.76, 4.19.77, 4.19.78, 4.19.79, 4.19.80, 4.19.81, 4.19.82, 4.19.83, 4.19.84, 4.19.85, 4.19.86, 4.19.87, 4.19.88, 4.19.89, 4.19.90, 4.19.91, 4.19.92, 4.19.93, 4.19.94, 4.19.95, 4.19.96, 4.19.97, 4.19.98, 4.19.99, 4.19.100, 4.19.101, 4.19.102, 4.19.103, 4.19.104, 4.19.105, 4.19.106, 4.19.107, 4.19.108, 4.19.109, 4.19.110, 4.19.111, 4.19.112, 4.19.113, 4.19.114, 4.19.115, 4.19.116, 4.19.117, 4.19.118, 4.19.118-2, 4.19.119, 4.19.120, 4.19.121, 4.19.122, 4.19.123, 4.19.124, 4.19.125, 4.19.126, 4.19.127, 4.19.128, 4.19.129, 4.19.130, 4.19.131, 4.19.132, 4.19.133, 4.19.134, 4.19.135, 4.19.136, 4.19.137, 4.19.138, 4.19.139, 4.19.140, 4.19.141, 4.19.142, 4.19.143, 4.19.144, 4.19.145, 4.19.146, 4.19.147, 4.19.148, 4.19.149, 4.19.150, 4.19.151, 4.19.152, 4.19.153, 4.19.154, 4.19.155, 4.19.156, 4.19.157, 4.19.158, 4.19.159, 4.19.160, 4.19.161, 4.19.162, 4.19.163, 4.19.164, 4.19.165, 4.19.166, 4.19.167, 4.19.168, 4.19.169, 4.19.170, 4.19.171, 4.19.172, 4.19.173, 4.19.174, 4.19.175, 4.19.176, 4.19.177, 4.19.178, 4.19.179, 4.19.180, 4.19.181, 4.19.182, 4.19.183, 4.19.184, 4.19.185, 4.19.186, 4.19.187, 4.19.188, 4.19.189, 4.19.190, 4.19.191, 4.19.192, 4.19.193, 4.19.194, 4.19.195, 4.19.196, 4.19.197, 4.19.198, 4.19.199, 4.19.200, 4.19.201, 4.19.202, 4.19.203, 4.19.204, 4.19.205, 4.19.206, 4.19.207, 4.19.208, 4.19.209, 4.19.210, 4.19.211, 4.19.212, 4.19.213, 4.19.214, 4.19.215, 4.19.216, 4.19.217, 5.4, 5.4.0, 5.4.0 rc6, 5.4.1, 5.4.2, 5.4.3, 5.4.4, 5.4.5, 5.4.6, 5.4.7, 5.4.8, 5.4.9, 5.4.10, 5.4.11, 5.4.12, 5.4.13, 5.4.14, 5.4.15, 5.4.16, 5.4.17, 5.4.18, 5.4.19, 5.4.20, 5.4.21, 5.4.22, 5.4.23, 5.4.24, 5.4.25, 5.4.26, 5.4.27, 5.4.28, 5.4.29, 5.4.30, 5.4.31, 5.4.32, 5.4.33, 5.4.34, 5.4.35, 5.4.36, 5.4.37, 5.4.38, 5.4.39, 5.4.40, 5.4.41, 5.4.42, 5.4.43, 5.4.44, 5.4.45, 5.4.46, 5.4.47, 5.4.48, 5.4.49, 5.4.50, 5.4.51, 5.4.52, 5.4.53, 5.4.54, 5.4.55, 5.4.56, 5.4.57, 5.4.58, 5.4.59, 5.4.60, 5.4.61, 5.4.62, 5.4.63, 5.4.64, 5.4.65, 5.4.66, 5.4.67, 5.4.68, 5.4.69, 5.4.70, 5.4.71, 5.4.72, 5.4.73, 5.4.74, 5.4.75, 5.4.76, 5.4.77, 5.4.78, 5.4.79, 5.4.80, 5.4.81, 5.4.82, 5.4.83, 5.4.84, 5.4.85, 5.4.86, 5.4.87, 5.4.88, 5.4.89, 5.4.90, 5.4.91, 5.4.92, 5.4.93, 5.4.94, 5.4.95, 5.4.96, 5.4.97, 5.4.98, 5.4.99, 5.4.100, 5.4.101, 5.4.102, 5.4.103, 5.4.104, 5.4.105, 5.4.106, 5.4.107, 5.4.108, 5.4.109, 5.4.110, 5.4.111, 5.4.112, 5.4.113, 5.4.114, 5.4.115, 5.4.116, 5.4.117, 5.4.118, 5.4.119, 5.4.120, 5.4.121, 5.4.122, 5.4.123, 5.4.124, 5.4.125, 5.4.126, 5.4.127, 5.4.128, 5.4.129, 5.4.130, 5.4.131, 5.4.132, 5.4.133, 5.4.134, 5.4.135, 5.4.136, 5.4.137, 5.4.138, 5.4.139, 5.4.140, 5.4.141, 5.4.142, 5.4.143, 5.4.144, 5.4.145, 5.4.146, 5.4.147, 5.4.148, 5.4.149, 5.4.150, 5.4.151, 5.4.152, 5.4.153, 5.4.154, 5.4.155, 5.4.156, 5.4.157, 5.4.158, 5.4.159, 5.4.160, 5.4.161, 5.10, 5.10 rc1, 5.10 rc2, 5.10 rc3, 5.10 rc4, 5.10 rc5, 5.10 rc7, 5.10.1, 5.10.2, 5.10.3, 5.10.4, 5.10.5, 5.10.6, 5.10.7, 5.10.8, 5.10.9, 5.10.10, 5.10.11, 5.10.12, 5.10.13, 5.10.14, 5.10.15, 5.10.16, 5.10.17, 5.10.18, 5.10.19, 5.10.20, 5.10.21, 5.10.22, 5.10.23, 5.10.24, 5.10.25, 5.10.26, 5.10.27, 5.10.28, 5.10.29, 5.10.30, 5.10.31, 5.10.32, 5.10.33, 5.10.34, 5.10.35, 5.10.36, 5.10.37, 5.10.38, 5.10.39, 5.10.40, 5.10.41, 5.10.42, 5.10.43, 5.10.44, 5.10.45, 5.10.46, 5.10.47, 5.10.48, 5.10.49, 5.10.50, 5.10.51, 5.10.52, 5.10.53, 5.10.54, 5.10.55, 5.10.56, 5.10.57, 5.10.58, 5.10.59, 5.10.60, 5.10.61, 5.10.62, 5.10.63, 5.10.64, 5.10.65, 5.10.66, 5.10.67, 5.10.68, 5.10.69, 5.10.70, 5.10.71, 5.10.72, 5.10.73, 5.10.74, 5.10.75, 5.10.76, 5.10.77, 5.10.78, 5.10.79, 5.10.80, 5.10.81, 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, 5.16 rc1, 5.16 rc2, 5.16 rc3, 5.16 rc4, 5.16 rc5, 5.16 rc6, 5.16 rc8
External links
https://git.kernel.org/stable/c/b20ec58f8a6f4fef32cc71480ddf824584e24743
https://git.kernel.org/stable/c/b0e44dfb4e4c699cca33ede431b8d127e6e8d661
https://git.kernel.org/stable/c/9c177eee116cf888276d3748cb176e72562cfd5c
https://git.kernel.org/stable/c/8823ea27fff6084bbb4bc71d15378fae0220b1d8
https://git.kernel.org/stable/c/daf972118c517b91f74ff1731417feb4270625a4
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.218
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.82
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.5
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.162
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.
