CVE-2021-28698
Assigner: XEN
Published: 2021-08-27T18:32:13
State: PUBLISHED
affected: product: xen
vendor: Xen
versions: status: affected
version: 4.14.x
product: xen
vendor: Xen
versions: lessThan: 4.12
status: unknown
version: unspecified
versionType: custom
lessThan: unspecified
status: affected
version: 4.15.x
versionType: custom
lessThan: unspecified
status: unaffected
version: next of xen-unstable
versionType: custom
product: xen
vendor: Xen
versions: status: affected
version: 4.13.x
product: xen
vendor: Xen
versions: status: affected
version: 4.11.x
product: xen
vendor: Xen
versions: status: affected
version: 4.12.x
credits: value: {'credit_data': {'description': {'description_data': [{'lang': 'eng', 'value': 'This issue was discovered by Andrew Cooper of Citrix.'}]}}}
descriptions: value: long running loops in grant table handling In order to properly monitor resource use, Xen maintains information on the grant mappings a domain may create to map grants offered by other domains. In the process of carrying out certain actions, Xen would iterate over all such entries, including ones which aren't in use anymore and some which may have been created but never used. If the number of entries for a given domain is large enough, this iterating of the entire table may tie up a CPU for too long, starving other domains or causing issues in the hypervisor itself. Note that a domain may map its own grants, i.e. there is no need for multiple domains to be involved here. A pair of "cooperating" guests may, however, cause the effects to be more severe.
metrics: other: content: description: description_data: value: Malicious or buggy guest kernels may be able to mount a Denial of
Service (DoS) attack affecting the entire system.
type: unknown
problemTypes: descriptions: description: unknown
type: text