#VU92379 Division by zero in Linux kernel - CVE-2021-47584

Vulnerability identifier: #VU92379

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-2021-47584

CWE-ID: CWE-369

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 division by zero error within the ioc_timer_fn() function in block/blk-iocost.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, 5.10.37, 5.10.38, 5.10.39, 5.10.40, 5.10.41, 5.10.42, 5.10.43, 5.10.44, 5.10.45, 5.10.46, 5.10.47, 5.10.48, 5.10.49, 5.10.50, 5.10.51, 5.10.52, 5.10.53, 5.10.54, 5.10.55, 5.10.56, 5.10.57, 5.10.58, 5.10.59, 5.10.60, 5.10.61, 5.10.62, 5.10.63, 5.10.64, 5.10.65, 5.10.66, 5.10.67, 5.10.68, 5.10.69, 5.10.70, 5.10.71, 5.10.72, 5.10.73, 5.10.74, 5.10.75, 5.10.76, 5.10.77, 5.10.78, 5.10.79, 5.10.80, 5.10.81, 5.10.82, 5.10.83, 5.10.84, 5.10.85, 5.10.86, 5.10.87, 5.15, 5.15 rc1, 5.15 rc2, 5.15 rc3, 5.15 rc4, 5.15 rc5, 5.15 rc6, 5.15 rc7, 5.15.0, 5.15.1, 5.15.2, 5.15.3, 5.15.4, 5.15.5, 5.15.6, 5.15.7, 5.15.8, 5.15.9, 5.15.10, 5.16 rc1, 5.16 rc2, 5.16 rc3, 5.16 rc4, 5.16 rc5, 5.16 rc6, 5.16 rc8

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External links
https://git.kernel.org/stable/c/a7c80674538f15f85d68138240aae440b8039519
https://git.kernel.org/stable/c/3a1a4eb574178c21241a6200f4785572e661c472
https://git.kernel.org/stable/c/edaa26334c117a584add6053f48d63a988d25a6e
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.10.88
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.11
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.16

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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.