CVE-2021-28712
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…
Does this matter?
Lower severity and a low EPSS score (0.33%). Track it; it rarely justifies an emergency change on its own.
Description
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
- CVSS 3.1
- 6.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
- EPSS
- 0.33% probability · 26th percentile
- CISA KEV
- Not listed
- Affected
- xen/xen · debian/debian linux
- Source
- security@xen.org
References
- https://lists.debian.org/debian-lts-announce/2022/03/msg00011.htmlThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.htmlThird Party Advisory
- https://www.debian.org/security/2022/dsa-5050Third Party Advisory
- https://www.debian.org/security/2022/dsa-5096Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-391.txtPatch, Vendor Advisory
- https://lists.debian.org/debian-lts-announce/2022/03/msg00011.htmlThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/03/msg00012.htmlThird Party Advisory
- https://www.debian.org/security/2022/dsa-5050Third Party Advisory
- https://www.debian.org/security/2022/dsa-5096Third Party Advisory
- https://xenbits.xenproject.org/xsa/advisory-391.txtPatch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.