“Juniper allowed it to propagate to peers, until it ultimately hit Arista devices that did not have (or contained faulty) BGP error tolerance code.”
One corrupted BGP attribute hit about 100 networks, including Starlink and Zscaler. Juniper protected its own session and passed the bad message on to its peers. Arista boxes reset on contact. Juniper’s own docs say its error handling does not inspect every part of a message.