The German unit of the Russian oil giant is obliged - alongside other companies operating so-called critical infrastructure - to report such incidents to the cyber security watchdog.
BSI has offered to Rosneft Deutschland support in analysis and restoring the systems, Die Welt reports.
Security sources suspect that the hacker collective «Anonymous» was behind the attack, which is not affecting Rosneft's ongoing business. However, the systems are affected, with various processes being disrupted, including the possibility of closing contracts, Die Welt reports.
After Russia invaded Ukraine at the end of February, the «Anonymous» group said it was launching a «cyber war» against Russia.
The hacker group has claimed it had hacked the websites of gas giant Gazprom, the state-controlled RT news agency, and many government agencies in Russia and Belarus, including the Kremlin's website.
After the cyberattack on Rosneft's German unit, the German watchdog BSI issued a cyber security warning to other companies in the oil industry in the country, Die Welt reported.
Supply of petroleum hasn't been disrupted, according to the newspaper's report, which added that Rosneft Deutschland had not responded to a request for comment.
Early last month, before Russia's invasion of Ukraine, operations at the oil terminals of some of northwest Europe's biggest ports – including Germany's Hamburg – were disrupted by a large-scale cyberattack.
Antwerp in Belgium - Europe's 2nd-largest port after Rotterdam - and the major German port Hamburg were among those targeted in the cyberattack.
The disruption to oil terminal operations at major ports in northwest Europe came days after a cyberattack on a German oil storage and logistics firm disrupted fuel supply chains in Germany, where supermajor Shell was forced to reroute supply to alternative depots.
Author: Tsvetana Paraskova
