  We model the risk posed by a malicious cyber-attacker seeking to induce grid
insecurity by means of a load redistribution attack, while explicitly
acknowledging that such an actor would plausibly base its decision strategy on
imperfect information. More specifically, we introduce a novel formulation for
the cyber-attacker's decision-making problem and analyze the distribution of
decisions taken with randomly inaccurate data on the grid branch admittances or
capacities, and the distribution of their respective impact. Our findings
indicate that inaccurate admittance values most often lead to suboptimal
cyber-attacks that still compromise the grid security, while inaccurate
capacity values result in notably less effective attacks. We also find common
attacked cyber-assets and common affected physical-assets between all (random)
imperfect cyber-attacks, which could be exploited in a preventive and/or
corrective sense for effective cyber-physical risk management.
