Rogue backends can cause DoS of guests via high frequency events T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Xen offers the ability to run PV backends in regular unprivileged guests, typically referred to as "driver domains". Running PV backends in driver domains has one primary security advantage: if a driver domain gets compromised, it doesn't have the privileges to take over the system. However, a malicious driver domain could try to attack other guests via sending events at a high frequency leading to a Denial of Service in the guest due to trying to service interrupts for elongated amounts of time. There are three affected backends: * blkfront patch 1, CVE-2021-28711 * netfront patch 2, CVE-2021-28712 * hvc_xen (console) patch 3, CVE-2021-28713
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
Source: MITRE
Published: 2022-01-05
Updated: 2022-04-06
Type: NVD-CWE-noinfo
Base Score: 2.1
Vector: AV:L/AC:L/Au:N/C:N/I:N/A:P
Impact Score: 2.9
Exploitability Score: 3.9
Severity: LOW
Base Score: 6.5
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
Impact Score: 4
Exploitability Score: 2
Severity: MEDIUM