Side-Channel Attacks

Brad Sollar
Chief Technical Officer

February 28, 2023

Hypervisors can be compromised by side-channel attacks where a malicious attacker can be co-located on the same physical server as a vulnerable workload and the attacker will be able to exfiltrate data from the victim with almost no indicators of compromise (IOC).

Spectre and Meltdown are two famous side-channel attacks that happened in the 2018 timeframe, but in March of 2021 researchers found new variants[1] of these attacks.

The only defense against these attacks is to apply patches or use stand-alone, bare-metal machines. The most secure way to defend against side-channel attacks is to not share hardware with other VMs, something that would make most traditional virtualization impossible to do as it’s a fundamental architectural design to share hardware between VMs in existing virtualization.

Side-Channel Protection

Metalvisor creates low-level isolation that makes side-channel attacks exponentially harder to exploit compared to traditional virtualization.

"The most secure way to defend against side-channel attacks is not to share hardware with other VMs"

Traditional virtualization time shares the physical hardware between virtual machines where speculative execution can be run against a CPU and may reveal private data to attackers.

Metalvisor isolates and dedicates the hardware from the time the virtual machine boots up, creating low-level defense-in-depth against these types of attacks. 

A penetration test was conducted by a third-party security consulting firm, InfusionPoints, in the spring of 2019. This rigorous test analyzed Metalvisor’s BIOS, secure boot, and forensic drive images to find weaknesses as well as multiple attacks from a tenant domain against other tenants and system resources.

The test found that Metalvisor significantly reduces the attack surface and mitigates side-channel attacks. Ultimately, the test was unable to successfully circumvent the protections provided by Metalvisor.