Security News > 2021 > July > Critical Microsoft Hyper-V bug could haunt orgs for a long time
The bug is in Hyper-V's network switch driver and affects Windows 10 and Windows Server 2012 through 2019.
The two researchers found the bug together and disclosed it privately to Microsoft.
The flaw stems from the fact that Hyper-V's virtual switch does not validate the value of an OID request that is intended for a network adapter.
An OID request can include hardware offloading, Internet Protocol security, and single root I/O virtualization requests.
"While processing OID requests, vmswitch traces their content for logging and debugging purposes; this also applies to OID SWITCH NIC REQUEST. However, due to its encapsulated structure, vmswitch needs to have special handling of this request and dereference OidRequest to trace the inner request as well. The bug is that vmswitch never validates the value of OidRequest and can thus dereference an invalid pointer," Harpaz explains.
"There are so many Windows Servers today that are vulnerable to well-known bugs, I won't be surprised if this bug stays unpatched for a very long time in organizations" - Ophir Harpaz.