#VU90094 Use-after-free in Linux kernel - CVE-2021-47280

Vulnerability identifier: #VU90094

Vulnerability risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-47280

CWE-ID: CWE-416

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 escalate privileges on the system.

The vulnerability exists due to a use-after-free error within the drm_getunique() function in drivers/gpu/drm/drm_ioctl.c. A local user can escalate privileges on the system.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.14, 4.14.0, 4.14.0 rc1, 4.14.1, 4.14.2, 4.14.3, 4.14.4, 4.14.5, 4.14.6, 4.14.7, 4.14.8, 4.14.9, 4.14.10, 4.14.11, 4.14.12, 4.14.13, 4.14.14, 4.14.15, 4.14.16, 4.14.17, 4.14.18, 4.14.19, 4.14.20, 4.14.21, 4.14.22, 4.14.23, 4.14.24, 4.14.25, 4.14.26, 4.14.27, 4.14.28, 4.14.29, 4.14.30, 4.14.31, 4.14.32, 4.14.33, 4.14.34, 4.14.35, 4.14.36, 4.14.37, 4.14.38, 4.14.39, 4.14.40, 4.14.41, 4.14.42, 4.14.43, 4.14.44, 4.14.45, 4.14.46, 4.14.47, 4.14.48, 4.14.49, 4.14.50, 4.14.51, 4.14.52, 4.14.53, 4.14.54, 4.14.55, 4.14.56, 4.14.57, 4.14.58, 4.14.59, 4.14.60, 4.14.61, 4.14.62, 4.14.63, 4.14.64, 4.14.65, 4.14.66, 4.14.67, 4.14.68, 4.14.69, 4.14.70, 4.14.71, 4.14.72, 4.14.73, 4.14.74, 4.14.75, 4.14.76, 4.14.77, 4.14.78, 4.14.79, 4.14.80, 4.14.81, 4.14.82, 4.14.83, 4.14.84, 4.14.85, 4.14.86, 4.14.87, 4.14.88, 4.14.89, 4.14.90, 4.14.91, 4.14.92, 4.14.93, 4.14.94, 4.14.95, 4.14.96, 4.14.97, 4.14.98, 4.14.99, 4.14.100, 4.14.101, 4.14.102, 4.14.103, 4.14.104, 4.14.105, 4.14.106, 4.14.107, 4.14.108, 4.14.109, 4.14.110, 4.14.111, 4.14.112, 4.14.113, 4.14.114, 4.14.115, 4.14.116, 4.14.117, 4.14.118, 4.14.119, 4.14.120, 4.14.121, 4.14.122, 4.14.123, 4.14.124, 4.14.125, 4.14.126, 4.14.127, 4.14.128, 4.14.129, 4.14.130, 4.14.131, 4.14.132, 4.14.133, 4.14.134, 4.14.135, 4.14.136, 4.14.137, 4.14.138, 4.14.139, 4.14.140, 4.14.141, 4.14.142, 4.14.143, 4.14.144, 4.14.145, 4.14.146, 4.14.147, 4.14.148, 4.14.149, 4.14.150, 4.14.151, 4.14.152, 4.14.153, 4.14.154, 4.14.155, 4.14.156, 4.14.157, 4.14.158, 4.14.159, 4.14.160, 4.14.161, 4.14.162, 4.14.163, 4.14.164, 4.14.165, 4.14.166, 4.14.167, 4.14.168, 4.14.169, 4.14.170, 4.14.171, 4.14.172, 4.14.173, 4.14.174, 4.14.175, 4.14.176, 4.14.177, 4.14.178, 4.14.179, 4.14.180, 4.14.181, 4.14.182, 4.14.183, 4.14.184, 4.14.185, 4.14.186, 4.14.187, 4.14.188, 4.14.189, 4.14.190, 4.14.191, 4.14.192, 4.14.193, 4.14.194, 4.14.195, 4.14.196, 4.14.197, 4.14.198, 4.14.199, 4.14.200, 4.14.201, 4.14.202, 4.14.203, 4.14.204, 4.14.205, 4.14.206, 4.14.207, 4.14.208, 4.14.209, 4.14.210, 4.14.211, 4.14.212, 4.14.213, 4.14.214, 4.14.215, 4.14.216, 4.14.217, 4.14.218, 4.14.219, 4.14.220, 4.14.221, 4.14.222, 4.14.223, 4.14.224, 4.14.225, 4.14.226, 4.14.227, 4.14.228, 4.14.229, 4.14.230, 4.14.231, 4.14.232, 4.14.233, 4.14.234, 4.14.235, 4.14.236, 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, 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, 5.10, 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, 5.12, 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, 5.12.9, 5.12.10, 5.13 rc1, 5.13 rc4, 5.13 rc5

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External links
https://git.kernel.org/stable/c/17dab9326ff263c62dab1dbac4492e2938a049e4
https://git.kernel.org/stable/c/7d233ba700ceb593905ea82b42dadb4ec8ef85e9
https://git.kernel.org/stable/c/b246b4c70c1250e7814f409b243000f9c0bf79a3
https://git.kernel.org/stable/c/491d52e0078860b33b6c14f0a7ac74ca1b603bd6
https://git.kernel.org/stable/c/f773f8cccac13c7e7bbd9182e7996c727742488e
https://git.kernel.org/stable/c/b436acd1cf7fac0ba987abd22955d98025c80c2b
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.237
https://mirrors.edge.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.195
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.44
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.11
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.4.126

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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.