CVE-2020-15567

CVE-2020-15567 is described in connected documents as a Xen hypervisor vulnerability: non-atomic modification of a live EPT PTE during mapping of guest EPT tables could expose partially written PTEs and be race-exploitable. Affected software is the Xen hypervisor (versions up to 4.13.x per descri...

non-atomic modification of live EPT PTE

ISSUE DESCRIPTION When mapping guest EPT nested paging tables, Xen would in some circumstances use a series of non-atomic bitfield writes. Depending on the compiler version and optimisation flags, Xen might expose a dangerous partially-written PTE to the hardware, which an attacker might be able ...

CVE-2020-15567: Concurrent Execution using Shared Resource with Improper Synchronization

An issue was discovered in Xen through 4.13.x, allowing Intel guest OS users to gain privileges or cause a denial of service because of non-atomic modification of a live EPT PTE. When mapping guest EPT nested paging tables, Xen would in some circumstances use a series of non-atomic bitfield write...