An issue was discovered in Xen through 4.13.x, allowing Arm guest OS users to cause a hypervisor crash because of a missing alignment check in VCPUOP_register_vcpu_info. The hypercall VCPUOP_register_vcpu_info is used by a guest to register a shared region with the hypervisor. The region will be mapped into Xen address space so it can be directly accessed. On Arm, the region is accessed with instructions that require a specific alignment. Unfortunately, there is no check that the address provided by the guest will be correctly aligned. As a result, a malicious guest could cause a hypervisor crash by passing a misaligned address. A malicious guest administrator may cause a hypervisor crash, resulting in a Denial of Service (DoS). All Xen versions are vulnerable. Only Arm systems are vulnerable. x86 systems are not affected.
2020-07-07T13:15:10.023
2024-11-21T05:05:44.610
Modified
CVSSv3.1: 6.5 (MEDIUM)
AV:L/AC:L/Au:N/C:N/I:N/A:C
3.9
6.9
| Type | Vendor | Product | Version/Range | Vulnerable? |
|---|---|---|---|---|
| Operating System | xen | xen | ≤ 4.13.1 | Yes |
| Operating System | debian | debian_linux | 10.0 | Yes |
| Operating System | fedoraproject | fedora | 31 | Yes |
| Operating System | fedoraproject | fedora | 32 | Yes |