They claim to have exploited a local file inclusion (LFI) vulnerability in Zimbra, a groupware email server and web client used on 34 Comcast mail servers, to access them and their content.
To prove their "conquest", they linked to a Pastebin post containing a list of the servers, and the exploit code they apparently used in the attack.
Databreaches.net reports that the post didn't include customer information, although one of the attackers implied that they have gotten their hands on a password database.
Comcast has yet to comment on the claims, but it seems that they are trying to protect their mail servers from further attacks now that the exploit code is public by shutting them down for the time being.
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