Hvci Bypass Link

The exploit chain Brine (CVE-2020-17087 & CVE-2020-1054) used a pool overflow to achieve arbitrary write and then patched the CI flag. This was a classic logical HVCI bypass. 3.2 Operational Bypass: Race Conditions in PTE Modification HVCI relies on the hypervisor to synchronize shadow page tables with the guest’s PTEs. If an attacker can modify a PTE after the hypervisor has validated it but before the CPU uses it, they can slip in a forbidden permission.

This is a attack.

HVCI ensures that kernel-mode code pages cannot be made writable and executable simultaneously. In simpler terms, it prevents an attacker (or a vulnerable driver) from injecting malicious shellcode into the kernel and executing it. Hvci Bypass