The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel does not properly context-switch IOPL on 64-bit PV Xen guests, which allows local guest OS users to gain privileges, cause a denial of service (guest OS crash), or obtain sensitive information by leveraging I/O port access.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Xen | Xen | 4.0.0 (including) | 4.0.0 (including) |