Core Insights - The Ryazan oil refinery in Russia, a significant asset for Rosneft, was forced to halt a major crude distillation unit due to a Ukrainian drone attack, resulting in a fire at the facility [1][2] - The affected unit, CDU-4, processes approximately 4 million metric tons of crude annually, accounting for about 80,000 barrels per day, which is nearly 25% of the refinery's total capacity [2] - The attack is part of a broader strategy by Ukraine to target Russian fuel infrastructure, which has implications for domestic fuel availability in Russia as winter approaches [3][4] Industry Impact - The Ryazan refinery processed 13.1 million tons of crude last year, producing 2.3 million tons of gasoline, 3.4 million tons of diesel, and 4.2 million tons of fuel oil, indicating a significant contribution to Russia's fuel supply [4] - A prolonged outage at the refinery could exacerbate fuel shortages in Russia, particularly during the winter months when heating demand is high [4] - While the immediate supply impact on global markets is limited, the symbolic nature of the attack raises the risk premium in oil prices and challenges the Kremlin's ability to safeguard its critical infrastructure [5]