#VU63584 Improper Resource Shutdown or Release in Linux kernel - CVE-2021-28715

Vulnerability identifier: #VU63584

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-28715

CWE-ID: CWE-404

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. A remote user can use a UDP connection on a fast interface to trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.15.0, 5.15.0

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External links
https://xenbits.xenproject.org/xsa/advisory-392.txt
https://www.debian.org/security/2022/dsa-5050
https://www.debian.org/security/2022/dsa-5096

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.