#VU63565 Resource exhaustion in Xen - CVE-2021-28713

Vulnerability identifier: #VU63565

Vulnerability risk: Low

CVSSv4.0: 5.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:H/E:U/U:Clear]

CVE-ID: CVE-2021-28713

CWE-ID: CWE-400

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Xen
Server applications / Virtualization software

Vendor: Xen Project

Description

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

The vulnerability exists due to improper limits for number of events driver domains could send to other guest VMs. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Xen: All versions

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External links
https://xenbits.xenproject.org/xsa/advisory-391.txt
https://www.debian.org/security/2022/dsa-5050
https://www.debian.org/security/2022/dsa-5096
https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html
https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html

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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.