HG612 has been hacked, just wonder whether I see any other advantages.
In what sense? Everyone talks about hacking the HG612 but it's usually meant in the traditional sense of 'modify functionality without documentation' rather than in the sense of trying to subvert the router into doing something malicious.
The HG612 as supplied by BT is not accessible from WAN or LAN. That means there is no attack vector external or internal. The firmware update is performed by the BT agent but that is accessing a server on a private IP address (one within BT's infrastructure) so that's not really a viable attack vector either.
All-in-all I doubt that an HG612 in its original BT form is vulnerable to criminal attack.
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Andrue Cope
Brackley, UK