Benno 
Errata patches for vmm have been released for OpenBSD 6.6.
A missing range check in the vmm pvclock allows a guest to write
to host memory.
Binary updates for the amd64 platform are available via the syspatch
utility. Source code patches can be found on the errata page:
https://www.openbsd.org/errata66.html
As these affect the kernel, a reboot will be needed after patching.
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