Adam Weinstein explains who had access to this information:
Quite possibly, the real damage this leak will do is to how the intelligence community operates. Last week, when the pundits were outraged at the revelations in The Washington Post’s expose on the intelligence community, much of it focused on how little agencies collaborate and share information. That is, when they find something important, they tend to keep it to themselves, rather than share it with the other 15 agencies that might be working on the same issue. The Post blamed this inability to share data, and the community’s inability to understand the sheer volume of data it collects, on several intelligence failures in recent months.
Think about what WikiLeaks has done, now. They have essentially told the entire IC that anything they write or say or make available to the broader defense community is, essentially, fair game to be made public.
Most of what you see on WikiLeaks are military SIGACTS (significant activity reports). These are theoretically accessible by anyone in Iraq, Afghanistan, or the Tampa, Florida-based US Central Commandsoldiers and contractorswho have access to the military's most basic intranet for sensitive data, the Secret Internet Protocol Router Network (SIPRNet). Literally thousands of people in hundreds of locations could read them, and any one of them could be the source for WikiLeaks' data.