#VU93381 Race condition in Linux kernel - CVE-2021-47163
Vulnerability identifier: #VU93381
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-362
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 a race condition within the cleanup_bearer() and tipc_udp_disable() functions in net/tipc/udp_media.c, within the tipc_exit_net() function in net/tipc/core.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, 5.10, 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, 5.12, 5.12 rc1, 5.12 rc2, 5.12 rc3, 5.12 rc4, 5.12 rc6, 5.12 rc8, 5.12.1, 5.12.2, 5.12.3, 5.12.4, 5.12.5, 5.12.6, 5.12.7, 5.12.8, 5.13 rc1, 5.13 rc4, 5.13 rc5
External links
https://git.kernel.org/stable/c/d1f76dfadaf8f47ed1753f97dbcbd41c16215ffa
https://git.kernel.org/stable/c/5195ec5e365a2a9331bfeb585b613a6e94f98dba
https://git.kernel.org/stable/c/b9f5b7ad4ac3af006443f535b1ce7bff1d130d7d
https://git.kernel.org/stable/c/04c26faa51d1e2fe71cf13c45791f5174c37f986
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.42
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.9
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.124
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.
