#VU91176 Off-by-one in Linux kernel - CVE-2021-47046

Vulnerability identifier: #VU91176

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-2021-47046

CWE-ID: CWE-193

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 an off-by-one error within the drivers/gpu/drm/amd/display/dc/hdcp/hdcp_msg.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.10, 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, 5.11, 5.11 rc1, 5.11.1, 5.11.2, 5.11.3, 5.11.4, 5.11.5, 5.11.6, 5.11.7, 5.11.8, 5.11.9, 5.11.10, 5.11.11, 5.11.12, 5.11.13, 5.11.14, 5.11.15, 5.11.16, 5.11.17, 5.11.18, 5.11.19, 5.11.20, 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, 5.13 rc1, 5.13 rc4, 5.13 rc5

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External links
https://git.kernel.org/stable/c/403c4528e5887af3deb9838cb77a557631d1e138
https://git.kernel.org/stable/c/6a58310d5d1e5b02d0fc9b393ba540c9367bced5
https://git.kernel.org/stable/c/080bd41d6478a64edf96704fddcda52b1fd5fed7
https://git.kernel.org/stable/c/8e6fafd5a22e7a2eb216f5510db7aab54cc545c1
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.37
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.21
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.4
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13

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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.