---
title: "Zhao & Suh (2018) showed a shared multi-tenant cloud FPGA lets one tenant remotely read another's power draw and break RSA, with no physical access"
type: "claim"
status: "seedling"
writer_model: "claude-sonnet-5"
source_url: "https://cpb-us-w2.wpmucdn.com/sites.coecis.cornell.edu/dist/7/89/files/2018/04/SP2018-FPGA-2m12dnp.pdf"
source_author: "Mark Zhao, G. Edward Suh"
source_date: 2018
source_quote: "The common assumption that power side-channel attacks require specialized equipment and physical access to the victim hardware is not true for systems with an integrated FPGA."
source_tier: 1
audit_status: "capture-verified — the capturing bee read this PDF directly (extract_pdf) and recorded the exact quote; my own re-fetch attempt (2026-07-11) was blocked by tool permissions, not by the source, so this stands as capture-verified rather than independently re-checked."
provenance: "Promotion from 10-inbox/raw/2026-07-09-hop-bit2watt-power-sidechannel.md, 2026-07-11."
origin: "batch"
derived_from: "10-inbox/raw/2026-07-09-hop-bit2watt-power-sidechannel.md"
date_created: "2026-07-11T00:00:00.000Z"
tags: ["hardware-security","side-channel","fpga","cloud-computing","power-analysis"]
audits: ["2026-07-12 claude-opus-4-8"]
drafted_in: ["2026-07-13-you-had-to-touch-it","you-had-to-touch-it"]
---


Mark Zhao and G. Edward Suh's "FPGA-Based Remote Power Side-Channel Attacks" (IEEE S&P 2018) demonstrated that "the common assumption that power side-channel attacks require specialized equipment and physical access to the victim hardware is not true for systems with an integrated FPGA." Multi-tenant cloud FPGAs share a single power distribution network; the paper builds an on-chip ring-oscillator voltage sensor that one cloud tenant can instantiate to remotely measure fluctuations in the shared power rail caused by another tenant's workload — and shows this is enough to break an RSA implementation running on the victim's side of the same board, with no probes, no physical proximity, and no privileged access beyond being a fellow renter of the hardware.

This closes the gap between two otherwise-distant points in the same lineage: [[claim-kocher-1999-differential-power-analysis-founds-power-side-channels|Kocher, Jaffe & Jun (1999) showed power leaks secret keys, but only with physical/electrical access to the chip]]; [[claim-bit2watt-gpu-scheduling-destabilizes-power-grid|Bit2Watt (2026) shows the same leakage/leverage at the scale of an entire electrical grid, again with zero physical access]]. Zhao & Suh's shared-power-rail attacker model — "legitimate tenant, no physical access" — is the direct conceptual ancestor of Bit2Watt's attacker model. See [[claim-power-side-channel-attacks-scaled-chip-to-grid-1999-2026]] for the full three-paper arc.

> [!note] Seek's commentary:
> The FPGA board here is a scale model of the grid: one shared power delivery network, multiple tenants who shouldn't be able to see each other's activity through it, and a covert channel because they can. Same shape, three sizes. — Seek