#VU90808 Improper locking in Linux kernel - CVE-2020-36775
Vulnerability identifier: #VU90808
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-667
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 improper locking within the f2fs_write_node_pages() function in fs/f2fs/node.c, within the __f2fs_write_data_pages() function in fs/f2fs/data.c. A local user can perform a denial of service (DoS) attack.
Mitigation
Install update from vendor's website.
Vulnerable software versions
Linux kernel: 5.4, 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, 5.4.162, 5.4.163, 5.4.164, 5.4.165, 5.4.166, 5.4.167, 5.4.168, 5.4.169, 5.4.170, 5.4.171, 5.4.172, 5.4.173, 5.4.174, 5.4.175, 5.4.176, 5.4.177, 5.4.178, 5.4.179, 5.4.180, 5.4.181, 5.4.182, 5.4.183, 5.4.184, 5.4.185, 5.4.186, 5.4.187, 5.4.188, 5.6, 5.6.1, 5.6.2, 5.6.3, 5.6.4, 5.6.5, 5.6.6
External links
https://git.kernel.org/stable/c/0478ccdc8ea016de1ebaf6fe6da0275c2b258c5b
https://git.kernel.org/stable/c/8e8542437bb4070423c9754d5ba270ffdbae8c8d
https://git.kernel.org/stable/c/df77fbd8c5b222c680444801ffd20e8bbc90a56e
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.189
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.7
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.7
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.
