#VU89256 Memory leak in Linux kernel - CVE-2021-47122


| Updated: 2025-05-14

Vulnerability identifier: #VU89256

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-2021-47122

CWE-ID: CWE-401

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 memory leak within the caif_device_notify() function in net/caif/caif_dev.c. A local user can perform a denial of service attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.4, 4.4.0, 4.4.0-57, 4.4.1, 4.4.2, 4.4.3, 4.4.4, 4.4.5, 4.4.6, 4.4.7, 4.4.8, 4.4.9, 4.4.10, 4.4.11, 4.4.12, 4.4.13, 4.4.14, 4.4.15, 4.4.16, 4.4.17, 4.4.18, 4.4.19, 4.4.20, 4.4.21, 4.4.22, 4.4.23, 4.4.24, 4.4.25, 4.4.26, 4.4.27, 4.4.28, 4.4.29, 4.4.30, 4.4.31, 4.4.32, 4.4.33, 4.4.34, 4.4.35, 4.4.36, 4.4.37, 4.4.38, 4.4.39, 4.4.40, 4.4.41, 4.4.42, 4.4.43, 4.4.44, 4.4.45, 4.4.46, 4.4.47, 4.4.48, 4.4.49, 4.4.50, 4.4.51, 4.4.52, 4.4.53, 4.4.54, 4.4.55, 4.4.56, 4.4.57, 4.4.58, 4.4.59, 4.4.60, 4.4.61, 4.4.62, 4.4.63, 4.4.64, 4.4.65, 4.4.66, 4.4.67, 4.4.68, 4.4.69, 4.4.70, 4.4.71, 4.4.72, 4.4.73, 4.4.74, 4.4.75, 4.4.76, 4.4.77, 4.4.78, 4.4.79, 4.4.80, 4.4.81, 4.4.82, 4.4.83, 4.4.84, 4.4.85, 4.4.86, 4.4.87, 4.4.88, 4.4.89, 4.4.90, 4.4.91, 4.4.92, 4.4.93, 4.4.94, 4.4.95, 4.4.96, 4.4.97, 4.4.98, 4.4.99, 4.4.100, 4.4.101, 4.4.102, 4.4.103, 4.4.104, 4.4.105, 4.4.106, 4.4.107, 4.4.108, 4.4.109, 4.4.110, 4.4.111, 4.4.112, 4.4.113, 4.4.114, 4.4.115, 4.4.116, 4.4.117, 4.4.118, 4.4.119, 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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, 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, 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External links
https://git.kernel.org/stable/c/b042e2b2039565eb8f0eb51c14fbe1ef463c8cd8
https://git.kernel.org/stable/c/9348c1f10932f13b299cbc8b1bd5f780751fae49
https://git.kernel.org/stable/c/4bca2034b41c15b62d47a19158bb76235fd4455d
https://git.kernel.org/stable/c/3be863c11cab725add9fef4237ed4e232c3fc3bb
https://git.kernel.org/stable/c/f52f4fd67264c70cd0b4ba326962ebe12d9cba94
https://git.kernel.org/stable/c/af2806345a37313f01b1c9f15e046745b8ee2daa
https://git.kernel.org/stable/c/6a0e317f61094d377335547e015dd2ff12caf893
https://git.kernel.org/stable/c/b53558a950a89824938e9811eddfc8efcd94e1bb
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.236
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.194
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.272
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.9.272
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.43
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.10
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.125


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.


Latest bulletins with this vulnerability