CVE-2021-28698

Name of the Vulnerable Software and Affected Versions Xen (affected versions not specified)

Description The issue is related to long running loops in grant table handling. Xen maintains information on grant mappings a domain may create to map grants offered by other domains. When carrying out certain actions, Xen iterates over all such entries, including ones that aren't in use anymore and some that may have been created but never used. If the number of entries for a given domain is large enough, this iteration may tie up a CPU for too long, starving other domains or causing issues in the hypervisor itself. A domain may map its own grants, and a pair of "cooperating" guests may cause the effects to be more severe.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.