According to Eric Margolis the Soviets deliberately caused a panic in Cairo and Damascus with doctored intelligence and that led to the military build-up that caused Israel to… Well, you know the rest of the story.
Margolis posits a couple reasons why the Soviets might have done this:
- They actually believed that Egypt and Syria could win this type of conflict,
- They were setting up the Arabs for failure to drive them further into Moscow’s arms,
- Pro-Israeli KGB agents were acting on their own.
Any other ideas? I really recommend the whole article. It also touches on the curious saga of the USS Liberty.