#VU91543 Improper locking in Linux kernel - CVE-2021-47055

Vulnerability identifier: #VU91543

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-2021-47055

CWE-ID: CWE-667

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 improper locking within the mtdchar_ioctl() function in drivers/mtd/mtdchar.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

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External links
https://git.kernel.org/stable/c/f4d28d8b9b0e7c4ae04214b8d7e0b0466ec6bcaf
https://git.kernel.org/stable/c/9625b00cac6630479c0ff4b9fafa88bee636e1f0
https://git.kernel.org/stable/c/f73b29819c6314c0ba8b7d5892dfb03487424bee
https://git.kernel.org/stable/c/75ed985bd6c8ac1d4e673e93ea9d96c9908c1d37
https://git.kernel.org/stable/c/5880afefe0cb9b2d5e801816acd58bfe91a96981
https://git.kernel.org/stable/c/7b6552719c0ccbbea29dde4be141da54fdb5877e
https://git.kernel.org/stable/c/077259f5e777c3c8821f6b41dee709fcda27306b
https://git.kernel.org/stable/c/a08799d3e8c8088640956237c183f83463c39668
https://git.kernel.org/stable/c/1e97743fd180981bef5f01402342bb54bf1c6366

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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.