The following gets into spoilers for Venom, so if you haven't yet seen Ruben Fleischer's origin story for Eddie Brock and his symbiote buddy, bail now and come back after you have screened it!
The new Venom movie had to get through a LOT of story as it set up the crucial bond between Eddie Brock (Tom Hardy) and the alien symbiote known as Venom. Along the way, the movie probably left a few major questions unanswered, one being how that Malaysian woman infected with the symbiote known as Riot survived the 6 month time jump at the start of the movie. Ruben Fleischer addressed this recently, stating:
Our idea was that Riot was using up the life force of whoever he took, and then he jumped ship when he'd consumed them and then find a new host to carry him further on his journey. [The old lady is] one of our few -- hopefully -- few logic bumps. But we had to have a passage of time in order to show Eddie's downfall, and that was the one thing that doesn't entirely track. But I like to think that old lady was going around murdering all throughout Malaysia, and she was just having a good old time just shooting shards through different people in Malaysia.
But as GameSpot points out, this means that Riot was on the loose in Malaysia for all of that time. Was Riot communicating with the old lady? Was she a total zombie? Did her family not notice? There are similar questions that one can raise about a little girl possessed by Riot in the movie. Basically, the movie needed to get Riot to San Francisco. But it don't quite know how to do that properly.
Seriously, though, the mystery of the old lady is the least of the problems in Venom. We still need to know how Carlton Drake (Riz Ahmed) climbed the scientific ladder when he is the least competent corporate suit we've seen in a movie in years. Also, why on Earth did Eddie's editor send his pitbull journalist in to do a puff piece assignment... and then FIRE Eddie when Brock did exactly what Brock is known to do?!