Journalists need to check their biases and ensure that everything they write is balanced. When mentioning that they might be Russian speakers, a good balancing sentence would be to point out countries which use the Russian language. Just throwing in "Russian speaker" after explicitly stating they're not sure which nation state did this is extremely unprofessional.
Sure, mention all the facts. Don't try to interpret them as "clues". If you have to, make sure you're not building a narrative without being absolutely sure.
Its not good journalism to go from `transport_http` to indicating that this is an attack by the Russian federation. That's not how you do good journalism. How many people will retain the fact that the author does NOT know which, if any, nation state did this?