That being said stab in the back doesn't involve antisemitism in Slavic languages. I have the same idiom in Polish, and it's just an idiom for betrayal.
It's also a common idiom in the German language, but in a different form: The Dolchstoß is associated with WWI and antisemitic ideas, while in den Rücken fallen (literally to fall into someone's back) is the linguistic backstab figure.