CVE-2021-28711: Medium severity xen xapi vulnerability
Last updated 25 April 2025
Other sources
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 hvcxen (console) patch 3, CVE-2021-28713
— Launchpad
Affected Software
Remediation
Patch Available
Event History
Frequently Asked Questions
What is the severity of CVE-2021-28711?
CVE-2021-28711 is classified as a high severity vulnerability due to the potential for denial of service attacks.
How do I fix CVE-2021-28711?
To fix CVE-2021-28711, upgrade to the patched versions of the Linux packages specified in your operating system's repository.
What are the affected systems for CVE-2021-28711?
CVE-2021-28711 affects various versions of Xen and Debian Linux operating systems.
What types of attacks can CVE-2021-28711 enable?
CVE-2021-28711 can enable denial of service (DoS) attacks against guests by leveraging rogue backends.
Can CVE-2021-28711 be exploited remotely?
Yes, CVE-2021-28711 can potentially be exploited remotely if untrusted backend services are allowed to operate in the system.