Criminals could potentially cause black-outs and mess with power grid configurations by exploiting flaws in a popular solar panel management system used by thousands of homes and businesses.

Details of how the attacks could be executed were kept under wraps while solar panel monitoring kit vendor Solar-Log distributed a patch for the flaws.

The threat is substantial because, as the company boasts, its eponymous management system runs globally on roughly 229,300 solar plants that typically pump out 5.66TWh of electrical energy a day, or so we're told.

But according to Sergey Gordeychik, security researcher and chief technology officer at Russian outfit Positive Security, attackers could break into the Solar-Log boxes and cause significant damage on centralised power grids.

"For instance a massive attack can cause power grid reconfiguration and chains of blackouts [and] bad guys can try to monetise it via blackmail," Goreychik said."

"At moment we can’t disclose more detail [about the vulnerabilities] because thousands of households around the globe are using vulnerable version of Solar-Log and can be attacked by cyber criminals.

Attackers could download Solar-Log configuration files for a variety of versions without being prevented by authentication, mess with user passwords, execute arbitrary code and even manipulate "specific power-generation related values".

This may under certain conditions mean trouble for smart grids where configurations could be changed and users could spoof the amount of power pumped back into grids by their solar installations, effectively scoring free cash.

The three separate flaws detailed here (PDF) related to configuration file and firmware handling processes and were fixed impressively a week after they were quietly reported by Positive Security through Germany's Computer Emergency Response Team (Bund).

The Russian hackers with a penchant for busting Supervisory Control and Data Acquisition (SCADA) systems did not ordinary spend much time considering threat vectors, Goreychik said, preferring to find and plug vulnerabilities.

Yet their penetration testing work against SCADA systems inevitably leads to the discovery of bugs with potentially life-threatening consequences. ®