Jorge Molina gave Betis a half-time lead after Antoine Griezmann's brilliant strike was disallowed at the other end.
Pabon doubled the lead but Sociedad roared back with three goals in 11 minutes from Carlos Vela, Inigo Martinez and Xabi Prieto, the latter with a penalty.
But Pabon's second secured a deserved share of the spoils for Betis, who more than played their part in a thrilling match.
Vela's early volley was tipped around the post by Adrian, who then had to gather Alberto de la Bella's effort from out wide as Sociedad started the game on the front foot.
Antonio Amaya blocked Imanol Agirretxe's shot before Adrian made another excellent save from Vela's close-range effort.
Sociedad were aggrieved in the 23rd minute when Griezmann ran onto Carlos Martinez's through-ball and let the ball drop before firing superbly past Adrian - only to be denied by a delayed and inaccurate offside flag.
Betis only had two long-range Pabon efforts, both over the bar, to their name by that point but should have been ahead when Benat's corner bypassed everybody in the six-yard box and dropped to Amaya beyond the far post but his volley was weak.
But the reprieve was short-lived as, after Agirretxe headed Vela's corner against the post at one end, Betis broke to the other and Joel Campbell's perfect through-ball found Molina, who stroked the ball past goalkeeper Claudio Bravo.
Molina broke into the box after a one-two with Pabon but was kept at bay by a combination of Inigo Martinez and Bravo.
A fluent counter-attack by Sociedad came to nothing as Carlos Martinez's overhit cross, the last kick of the first half, flashed across the face of goal and out of play.
The second half started with Campbell just over-hitting a pass almost identical to that which set up the goal, with Molina this time unable to reach it.
But it was 2-0 moments later when Benat's nicely weighted through-ball took a touch off defender Mikel Gonzalez, taking Bravo out of the game and allowing Pabon to tap home from close range.
Sociedad found an immediate response, though, as Vela hammered home Agirretxe's knockdown after Amaya had deflected De la Bella's cross up in the air.
Inigo Martinez equalised only 11 minutes into a second half which had started in frenetic fashion, heading Vela's cross back across goal to leave Adrian helpless.
And the turnaround was completed just after the hour mark when Angel Lopez was penalised for handball and Xabi Prieto scooped the resulting penalty into the roof of the net.
But amazingly Betis were level just four minutes after that, Pabon exchanging passes with substitute Ruben Castro before finishing coolly across Bravo.
Vela was denied a second Sociedad penalty after throwing himself to the ground claiming contact from Jose Alberto Canas, but the former Arsenal forward's cross almost led to a fourth goal for his side soon afterwards. Agirretxe was unable to make contact and was on the ground when Griezmann's weak header bobbled across goal.
Amaya deflected Griezmann's low cross goal side of Adrian and across the goalmouth for a corner and De la Bella's leaping volley forced an excellent save from the keeper.
Amaya blocked substitute Diego Ifran's shot as the game finished all square.