The visitors twice led courtesy of Antoine Griezmann goals but Sociedad pegged them back on both occasions to prevent a third straight loss.
Sociedad's Gonzalo Castro wasted an excellent early chance by firing wide from close range, but otherwise it was mostly Valladolid until Griezmann's 37th-minute opener.
Griezmann showed quick reactions to pounce on a loose ball inside the box and shoot high into the roof of the net with the interval approaching.
However, Sociedad were level before the break as Ebert's 30-yard shot skidded off the turf and past Zubikarai.
La Real restored their lead through Griezmann's second as he bent a precise effort into the top corner just prior to the hour mark.
Yet again though, Sociedad could not hang on to collect maximum points as Oscar Gonzalez headed in his fifth of the season to reclaim parity for Valladolid.