Dutch security engineer Willem Westerhof has identified 21 vulnerabilities in the photovoltaic panels sold by SMA. The flaws range from easy-exploitable Denial-of-Service bugs to the usage of simple default passwords (0000) Some bugs need local access to use, but some allow remote exploitation via an Internet connection. The researcher claims the SMA flaws allow an attacker to damage the normal functioning of a solar power plant. The real damage would not come in the form of production and monetary loss for the solar plant’s owners, but the impromptu shock to the power grid itself.
Source: https://www.bleepingcomputer.com/news/security/cyber-attack-on-solar-panels-could-shut-down-power-grids-via-domino-effect/