Los Carbayones have so far generated €1.1 million towards paying off their immediate debts, with people in over 60 countries buying shares, a quarter of which have been acquired on the Internet.
A social media campaign to raise awareness has given the club a lifeline, but their future remains on a knife-edge.
"We are on the way, but there is still work to do," Oviedo president Toni Fidalgo told AS.
The club's biggest shareholder, Alberto Gonzalez, has fled Spain and is wanted by Interpol for fiscal fraud.
Oviedo ultimately need to raise over €4m to pay off their short-term debt, with €2.5m the target before the end of the year to escape insolvency.
However, around €2m must be raised by this Saturday to avoid going bankrupt. The club put shares on sale to the public at €10.75 per share on November 3.
To date, Oviedo have sold just over €278,000 in equity online despite their efforts to spread the word on social media platforms.