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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Evil PGP sigs thread must die. was Re: Stop it withputting your e-mail body in my MUA OT
At 3:15 PM -0400 2002/07/10, Andy Dills wrote: True enough. But you do significantly raise the bar. It's like putting a deadbolt lock on your front door -- maybe it's locked, and maybe it's not. But it's very presence will tend to deter a certain percentage of attackers.If people judge authenticity based on the simple fact that a message is signed, that's just as useless. Why wouldn't the spoofed email be signed with somebody else's key, to make it past all those people who merely check to see if it's signed? The _only_ way to verify authenticity is to check the signature. However, even if the door is locked, we all know that a sufficiently motivated attacker can get past *ANY* lock. If they can't break the lock itself, they break the door. If they can't break the door, they break a window. If they can't break a window, then they break a wall. But it is a pretty good deterrent for people who just walk around twiddling knobs. Nope. The only way to make this work is to sign all messages, and all messages that are not signed are automatically suspect. Indeed, even signed messages are at least somewhat suspect, and should always have the signature validated -- modern encryption/keyring management programs should make this fairly easy to make automatically happen by default.Therefore, you should only sign emails that contain information important enough that verification is necessary, otherwise nobody will check. -- Brad Knowles, <[email protected]> "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." -Benjamin Franklin, Historical Review of Pennsylvania.
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