#VU90439 Memory leak in Linux kernel - CVE-2021-47568

Vulnerability identifier: #VU90439

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-2021-47568

CWE-ID: CWE-401

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 memory leak within the get_file_stream_info() function in fs/ksmbd/smb2pdu.c. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.15, 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, 5.16 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/11e659827c3a2facb3a04e08cc97ff14d5091f51
https://git.kernel.org/stable/c/178ca6f85aa3231094467691f5ea1ff2f398aa8d
https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.6
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.