#VU91528 Improper locking in Linux kernel - CVE-2021-47185

Vulnerability identifier: #VU91528

Vulnerability risk: Low

CVSSv4.0: [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-2021-47185

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 flush_to_ldisc() function in drivers/tty/tty_buffer.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
http://git.kernel.org/stable/c/0380f643f3a7a61b0845cdc738959c2ad5735d61
http://git.kernel.org/stable/c/b1ffc16ec05ae40d82b6e373322d62e9d6b54fbc
http://git.kernel.org/stable/c/4c1623651a0936ee197859824cdae6ebbd04d3ed
http://git.kernel.org/stable/c/4f300f47dbcf9c3d4b2ea76c8554c8f360400725
http://git.kernel.org/stable/c/d491c84df5c469dd9621863b6a770b3428137063
http://git.kernel.org/stable/c/77e9fed33056f2a88eba9dd4d2d5412f0c7d1f41
http://git.kernel.org/stable/c/5c34486f04700f1ba04907231dce0cc2705c2d7d
http://git.kernel.org/stable/c/3968ddcf05fb4b9409cd1859feb06a5b0550a1c1

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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.