description: guests may exceed their designated memory limit When a guest is permitted to have close to 16TiB of memory, it may be able to issue hypercalls to increase its memory allocation beyond the administrator established limit. This is a result of a calculation done with 32-bit precision, which may overflow. It would then only be the overflowed (and hence small) number which gets compared against the established upper bound.
problem types: unknown
affected:
{
vendor: Xen
product: xen
versions:
version: 4.12.x, status: affected
}
{
vendor: Xen
product: xen
versions:
version: unspecified, lessThan: 4.12, status: unknown, versionType: custom
version: 4.14.x, status: affected, lessThan: unspecified, versionType: custom
version: next of 4.15.x, status: unaffected, lessThan: unspecified, versionType: custom
}
{
vendor: Xen
product: xen
versions:
version: xen-unstable, status: affected
}
{
vendor: Xen
product: xen
versions:
version: 4.13.x, status: affected
}
metrics:
other: [
type: unknown
content: {'description': {'description_data': [{'lang': 'eng', 'value': 'A guest may be able too allocate unbounded amounts of memory to itself.\nThis may result in a Denial of Service (DoS) affecting the entire host.'}]}}
]