Did the Cylons Attack All of the Colonies?

Question

In the re-imagined Battlestar Galactica series, the Cylons

nuked Caprica and attacked the Scorpion Fleet shipyard, destroying much of the Colonial fleet, save for Pegasus and Galactica and some civilian ships.

Would they have also attacked the other Colonial planets? Are there any references in or out of universe as to whether all planets had been attacked? Or was it just Caprica and the shipyard?

Answer 1

The entire premise of the series is that the civilization of the Twelve Colonies has been attacked and the Battlestar Galactica is protecting a fleet of approximately 50,000 survivors of all the colonies.

Direct reference is made to attacks on some of the colonies, from the pilot episode:

Adama: (over the intercom) Preliminary reports indicate a thermonuclear device in the fifty-megaton range was detonated over Caprica City thirty minutes ago. Nuclear detonations have been reported on the planets Aerlon, Picon, Saggitarion and Geminon. No reports on casualties, but they will be high.

So this is directly referencing five of the colonies having reports of attacks.

At the end of the miniseries Adama addresses the survivors at a ceremony on Galactica:

Adama: Are they the lucky ones? That's what you're thinking, isn't it? We're a long way from home. We've jumped way beyond the red line, into unchartered space. Limited supplies, limited fuel. No allies, and now, no hope? Maybe it would have been better for us to have died quickly, back on the Colonies with our families, instead of dying out here slowly, in the emptiness of dark space. Where shall we go? What shall we do? Life here began out there. Those are the first words of the sacred scrolls, and they were told to us by the Lords of Kobol, many countless centuries ago. And they made it perfectly clear that we are not alone in this universe. Elosha, there's a thirteenth colony of humankind, is there not?

I think it is fairly clear that the implication is that all twelve colonies were attacked and destroyed. This is reinforced by the fact that the council of the colonies is re-formed with representatives drawn from the survivors in the fleet, a representative from each of the former colonies.

Answer 2

In the TV movie The Plan (released after the series, but set as a parallel story to the first season and a half), we hear one of the Cylon hybrids reporting on the attacks while various scenes of destruction are also shown:

Progress reports arriving.
The farms of Aerilon are burning.
The beaches of Canceron are burning.
The plains of Leonis are burning.
The jungles of Scorpia are burning.
The pastures of Tauron are burning.
The harbors of Picon are burning.
The cities of Caprica are burning.
The oceans of Aquaria are burning.
The courthouses of Libran are burning.
The forests of Virgon are burning.
The Colonies of Man lie trampled at our feet.

While Sagittaron (in the same solar system as Libran and Scorpia) and Geminon (a twin planet of Caprica) are not mentioned, it seems pretty clear that all 12 colonies were attacked at the time.