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
| Link | Tags |
|---|---|
| https://xenbits.xenproject.org/xsa/advisory-391.txt | patch vendor advisory |
| https://www.debian.org/security/2022/dsa-5050 | third party advisory vendor advisory |
| https://lists.debian.org/debian-lts-announce/2022/03/msg00011.html | third party advisory mailing list |
| https://lists.debian.org/debian-lts-announce/2022/03/msg00012.html | third party advisory mailing list |
| https://www.debian.org/security/2022/dsa-5096 | third party advisory vendor advisory |