Re: PGP's "only for your eyes"

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[To: cypherpunks@toad.com]
[Subject: Re: PGP's "only for your eyes"]

Usuario Acceso2 <acceso2@diatel.upm.es> wrote:
	Maybe some of you already know about this.

	Whe reading PGP's "Only for your eyes" messages, the program
	creates a temporary file containing the plaintext in the
	directory where the cyphertext file is.

	So, don't worry about this option, it's quite useless.

The manual points out that you shouldn't rely on it. Its main purpose is
simply to prevent accidentally or automatically leaving the plaintext
lying around, not to actually securely guarantee that behaviour. After
all, you could always cut-and-paste the text, or (since you have the PGP
source) alter PGP to ignore the flag.

The real problem is not what it does, but what people *think* it might
do.

I take that back. When I check the manual, it doesn't say that it is
insecure. It really ought to. At least one of the books about PGP does
though, I know I've read it somewhere other than email.

Chris McAuliffe <cmca@alpha.c2.org> (No, not that one.)

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In article <199602062336.PAA24566@infinity.c2.org> cmca@alpha.c2.org (Chris McAuliffe) writes:

> 	Maybe some of you already know about this.
> 
> 	Whe reading PGP's "Only for your eyes" messages, the program
> 	creates a temporary file containing the plaintext in the
> 	directory where the cyphertext file is.
> 
> 	So, don't worry about this option, it's quite useless.
> 
> The manual points out that you shouldn't rely on it. Its main purpose is
> simply to prevent accidentally or automatically leaving the plaintext
> lying around, not to actually securely guarantee that behaviour. After
> all, you could always cut-and-paste the text, or (since you have the PGP
> source) alter PGP to ignore the flag.

I've gotten burned by this because it created a temp file over NFS.
If I'd been able to read the message with my mail reader "pgp -f", I
would not have disclosed the information.  The for your eyes only
option is more than useless, it's dangerous.

> The real problem is not what it does, but what people *think* it might
> do.
> 
> I take that back. When I check the manual, it doesn't say that it is
> insecure. It really ought to. At least one of the books about PGP does
> though, I know I've read it somewhere other than email.

David