varstored is a component of the Xapi toolstack handling UEFI Variables for a VM. It has a communication path with OVMF inside the VM involving mapping a buffer prepared by OVMF.

Within varstored, there were insufficient compiler barriers, creating TOCTOU issues with data in the shared buffer.

The exact vulnerable behaviour depends on the code generated by the compiler. In a build of varstored using default settings, the attacker can control an index used in a jump table.

varstored is a component of the Xapi toolstack handling UEFI Variables for a VM. It has a communication path with OVMF inside the VM involving mapping a buffer prepared by OVMF.

Within varstored, there were insufficient compiler barriers, creating TOCTOU issues with data in the shared buffer.

The exact vulnerable behaviour depends on the code generated by the compiler. In a build of varstored using default settings, the attacker can control an index used in a jump table.

Ein lokaler Angreifer kann mehrere Schwachstellen in Xen ausnutzen, um seine Rechte zu erweitern und einen nicht näher spezifizierten Angriff durchzuführen.