Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-08 Thread Craig Sanders
On Sat, Sep 06, 2003 at 11:32:04PM +1000, Russell Coker wrote: DNSBL's and spamassasin seem quite good at dealing with spam and are much less annoying. That combined with some new laws that are being enacted to combat spam should keep it to a managable level. oh, please tell me that these new

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-06 Thread Russell Coker
On Sat, 6 Sep 2003 06:56, david nicol wrote: Unlike TMDA's distributed profusion of extended addresses, a central RAPNAP (return address, peer network address pair) database only needs to send out a challenge when you change your outgoing SMTP server. In effect, a central server

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-06 Thread david nicol
On Sat, 2003-09-06 at 08:32, Russell Coker wrote: Here's how it works. Spammer creates account [EMAIL PROTECTED] and sends their first spam to a C-R system, when the challenge comes in they acknowledge it and from then on the C-R system does not bother them because they keep using the

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-06 Thread Andrew Suffield
On Sat, Sep 06, 2003 at 06:02:07PM -0500, david nicol wrote: Don't hate spammers, figure out a way to bill them. They are in business, they pay for things, they expect to be billed. Everyone who has considered sender-pays agrees that it provides a better solution than legislation. Again

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-05 Thread Russell Coker
On Thu, 4 Sep 2003 18:32, david nicol wrote: I've been trying to popularize a centralized challenge-response database since last fall. It seems to me that becoming a debian package maintainer for the software to use it would make sense. Unlike TMDA's distributed profusion of extended

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-05 Thread david nicol
On Fri, 2003-09-05 at 00:16, Russell Coker wrote: On Thu, 4 Sep 2003 18:32, david nicol wrote: I've been trying to popularize a centralized challenge-response database since last fall. It seems to me that becoming a debian package maintainer for the software to use it would make sense.

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-05 Thread Andrew Suffield
On Fri, Sep 05, 2003 at 03:56:16PM -0500, david nicol wrote: For challenge response to work it has to be annoying to lots of people. Anything that stops it being annoying will stop it working. That's why it is broken. Challenge-response, BY ITSELF ONLY, suffers from that problem. When

Re: tmda: Challenge-response is fundamentally broken

2003-09-04 Thread Tollef Fog Heen
* Kalle Kivimaa | And yes, I'm actually considering filing grave bugs against each | such list software package (I'm willing to live with such behaviour | being optional with the default being no response, if the | documentation says beware SPAM worms if you enable autoresponse). Please file a

Re: tmda: Challenge-response is fundamentally broken (RAPNAP)

2003-09-04 Thread david nicol
Hello I've been trying to popularize a centralized challenge-response database since last fall. It seems to me that becoming a debian package maintainer for the software to use it would make sense. Unlike TMDA's distributed profusion of extended addresses, a central RAPNAP (return address,

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-31 Thread Riku Voipio
On Sat, Aug 30, 2003 at 11:49:40PM +, Brian May wrote: 2. All checks have to be automatic, and there is no chance of manual review to ensure that the messages where geniune before bouncing it. Actually, I'm pretty sure SA is statistically better than an average person scanning subject lines

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-31 Thread Karsten M. Self
on Sat, Aug 30, 2003 at 09:41:39PM -0500, John Hasler ([EMAIL PROTECTED]) wrote: I wrote: This is about a quarter of my incoming mail. Karsten writes: Which? Bounces to spoofed senders, or improperly addressed mail? Bounces. Thanks. What prevents you from 550ing this at SMTP

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-31 Thread Craig Sanders
On Sat, Aug 30, 2003 at 10:42:17AM +1000, Brian May wrote: On Fri, Aug 29, 2003 at 03:48:13PM +1000, Craig Sanders wrote: the point that you keep on missing is that TMDA and similar programs send confirmation emails to innocent third-parties who did *NOT* send an email. TMDA and all

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-31 Thread Craig Sanders
On Sat, Aug 30, 2003 at 04:01:19PM +1000, Russell Coker wrote: Backup MX servers serve no useful purpose in the modern Internet, this is why big sites such as microsoft.com and hotmail.com don't have them. agreed. If you have a backup MX then it should know all the acceptable email

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-31 Thread Craig Sanders
On Sat, Aug 30, 2003 at 11:49:40PM +, Brian May wrote: On Sat, Aug 30, 2003 at 04:01:19PM +1000, Russell Coker wrote: That is the idea behind autorespoonders after all, to tell the sender that his mail didn't get through because it didn't meet some required criteria. A SMTP 550

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Russell Coker
On Sat, 30 Aug 2003 10:42, Brian May wrote: On Fri, Aug 29, 2003 at 03:48:13PM +1000, Craig Sanders wrote: the point that you keep on missing is that TMDA and similar programs send confirmation emails to innocent third-parties who did *NOT* send an email. TMDA and all C-R systems are

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Karsten M. Self
on Sat, Aug 30, 2003 at 10:42:17AM +1000, Brian May ([EMAIL PROTECTED]) wrote: On Fri, Aug 29, 2003 at 03:48:13PM +1000, Craig Sanders wrote: the point that you keep on missing is that TMDA and similar programs send confirmation emails to innocent third-parties who did *NOT* send an email.

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread John Hasler
Brian May writes: You saying that any SMTP MTA that sends bounces to unauthenticated E-Mail addresses is also broken? Karsten M. Self writes: At the very least, this is a small subset of the incoming mail. This is about a quarter of my incoming mail. -- John Hasler [EMAIL PROTECTED] Dancing

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Osamu Aoki
I think challenge response needs extra care. Anyway, current e-mail worm/virus incident is pretty bad. On Sat, Aug 30, 2003 at 07:44:56AM -0500, John Hasler wrote: Brian May writes: You saying that any SMTP MTA that sends bounces to unauthenticated E-Mail addresses is also broken?

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Brian May
On Sat, Aug 30, 2003 at 04:01:19PM +1000, Russell Coker wrote: That is the idea behind autorespoonders after all, to tell the sender that his mail didn't get through because it didn't meet some required criteria. A SMTP 550 code can convey all the information that is needed for bounces.

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Steve Lamb
On Sat, 30 Aug 2003 23:49:40 + Brian May [EMAIL PROTECTED] wrote: 1. The modular design of SMTP agents like postfix do not allow scanning of messages before the message has been accepted by the MTA at the SMTP session. I think you would have to add hooks into smtpd, but that is going to

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Steve Langasek
On Sat, Aug 30, 2003 at 05:26:59PM -0700, Steve Lamb wrote: On Sat, 30 Aug 2003 23:49:40 + Brian May [EMAIL PROTECTED] wrote: 1. The modular design of SMTP agents like postfix do not allow scanning of messages before the message has been accepted by the MTA at the SMTP session. I

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread Karsten M. Self
on Sat, Aug 30, 2003 at 07:44:56AM -0500, John Hasler ([EMAIL PROTECTED]) wrote: Brian May writes: You saying that any SMTP MTA that sends bounces to unauthenticated E-Mail addresses is also broken? Karsten M. Self writes: At the very least, this is a small subset of the incoming mail.

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-30 Thread John Hasler
I wrote: This is about a quarter of my incoming mail. Karsten writes: Which? Bounces to spoofed senders, or improperly addressed mail? Bounces. What prevents you from 550ing this at SMTP connect? The absence of any such connections. I'm on a dialup. -- John Hasler [EMAIL PROTECTED] (John

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread benfoley
On Friday 29 August 2003 09:28, Steve Lamb wrote: On Fri, 29 Aug 2003 00:36:57 -0700 Adam McKenna [EMAIL PROTECTED] wrote: Well, since we're pointing fingers, it's really SMTP that's broken by design, and all anti-spam programs (including C-R systems) are merely stopgap measures that try

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Steve Lamb
On Fri, 29 Aug 2003 16:31:59 + benfoley [EMAIL PROTECTED] wrote: On Friday 29 August 2003 09:28, Steve Lamb wrote: Oddly enough Spamassassin doesn't exasperate the problem. TDMA does. exacerbate is probably what you meant here. Quite so. 1:30am emails before the requisite

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Tore Anderson
* Adam McKenna #0, #1, #2 and #11 are basically opinion and rhetoric. Well. Let's take a look at what Karsten had to say about point #2, Misplaced burden: [...] «C-R may place the burden on third parties either inadvertently (via spoofed sender spam or virus mail), or deliberately

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Adam McKenna
On Fri, Aug 29, 2003 at 02:46:48AM +0200, Tore Anderson wrote: Earlier, you've stated that your time is precious. Well, so is mine. How dare you assume that the time I spent reviewing *your* callenge mail and deciding it was junk is less precious than the time you (could have) spent

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Steve Lamb
On Fri, 29 Aug 2003 00:36:57 -0700 Adam McKenna [EMAIL PROTECTED] wrote: Well, since we're pointing fingers, it's really SMTP that's broken by design, and all anti-spam programs (including C-R systems) are merely stopgap measures that try to make up for SMTP's shortcomings. Oddly enough

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Keegan Quinn
On Fri, Aug 29, 2003 at 04:31:59PM +, benfoley wrote: On Friday 29 August 2003 09:28, Steve Lamb wrote: On Fri, 29 Aug 2003 00:36:57 -0700 Adam McKenna [EMAIL PROTECTED] wrote: Well, since we're pointing fingers, it's really SMTP that's broken by design, and all anti-spam programs

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Karsten M. Self
on Thu, Aug 28, 2003 at 08:21:22AM -0700, Adam McKenna ([EMAIL PROTECTED]) wrote: On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: #2, Misplaced burden, is the reason for the 'grave' severity. People have a right to ask that unkown people that e-mail them confirm the

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Russell Coker
On Fri, 29 Aug 2003 11:16, Adam McKenna wrote: When the next address-spoofing virus hits, if I need to update my filters again, I'll make a better effort to do it ASAP instead of letting it go for several days. Why not make your tmda package depend on amavis-new and clamav-freshclam? If they

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Lars Wirzenius
reassign 207300 humanity thanks On pe, 2003-08-29 at 10:36, Adam McKenna wrote: Well, since we're pointing fingers, it's really SMTP that's broken by design, and all anti-spam programs (including C-R systems) are merely stopgap measures that try to make up for SMTP's shortcomings. The fact

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Craig Sanders
On Thu, Aug 28, 2003 at 08:21:22AM -0700, Adam McKenna wrote: On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: #2, Misplaced burden, is the reason for the 'grave' severity. People have a right to ask that unkown people that e-mail them confirm the e-mail. the point that

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Adam McKenna
On Fri, Aug 29, 2003 at 12:12:58PM +1000, Russell Coker wrote: On Fri, 29 Aug 2003 11:16, Adam McKenna wrote: When the next address-spoofing virus hits, if I need to update my filters again, I'll make a better effort to do it ASAP instead of letting it go for several days. Why not make

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Adam McKenna
On Fri, Aug 29, 2003 at 03:48:13PM +1000, Craig Sanders wrote: the point that you keep on missing is that TMDA and similar programs send confirmation emails to innocent third-parties who did *NOT* send an email. Really? TMDA and all C-R systems are broken-by-design, just as many stupid

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Brian May
On Fri, Aug 29, 2003 at 01:42:53AM +1000, Russell Coker wrote: PS Before someone raises the issue of license of viruses. I believe that anyone who distributes a virus does so with the desire that it be installed on as many systems as possible and that the implied license permits you to

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-29 Thread Brian May
On Fri, Aug 29, 2003 at 03:48:13PM +1000, Craig Sanders wrote: the point that you keep on missing is that TMDA and similar programs send confirmation emails to innocent third-parties who did *NOT* send an email. TMDA and all C-R systems are broken-by-design, just as many stupid end-user

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Adam McKenna
On Wed, Aug 27, 2003 at 05:40:46PM -0700, Don Armstrong wrote: On Wed, 27 Aug 2003, Adam McKenna wrote: TMDA does not ship with any defaults, except a couple of customizable text files (templates). It is entirely up to the user to create a TMDA configuration along with his own whitelist

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Rico -mc- Gloeckner
On Wed, Aug 27, 2003 at 05:40:46PM -0700, Don Armstrong wrote: If possible, perhaps you could consider whitelisting common debian.org address by default? [Things like [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED], etc.] And would probably defeat the purpose since spammers would know

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Karsten M. Self
First note: ISP mailbox overflow due to Sobig.F knocked me off a few Debian lists, I've just resubscribed. I've got a partial copy of this thread thanks to a friend who forwarded it to me. I've also been following the discussion in the d-d archives and BTS. Thanks to all who've commented on

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Karsten M. Self
on Thu, Aug 28, 2003 at 08:56:36AM +0200, Rico -mc- Gloeckner ([EMAIL PROTECTED]) wrote: On Wed, Aug 27, 2003 at 05:40:46PM -0700, Don Armstrong wrote: If possible, perhaps you could consider whitelisting common debian.org address by default? [Things like [EMAIL PROTECTED], [EMAIL

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Steve Lamb
Just some additional data points as I have been following this and other related C-R threads for a while now. On Thu, 28 Aug 2003 12:35:25 +0100 Karsten M. Self kmself@ix.netcom.com wrote: [ Snip ] Specific to my own experience: over half the C-R challenges (TMDA or otherwise) I've

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Andreas Metzler
Karsten M. Self kmself@ix.netcom.com wrote: [...] SpamAssassin achieves a false-positive rate (non-spam reported as spam) of 5% with a default threshold of 5. This can be dramatically improved using a whitelist, to ~98% in my experience. This is not the best performance of all filters, so

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Hamish Moffatt
On Wed, Aug 27, 2003 at 05:35:14PM +0200, Florian Weimer wrote: That's why it's better to get rid of generic MX secondaries (IOW secondaries which are not under you administrative control). The Which is fine if you're lucky enough to have root on a set of conveniently distributed hosts...

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Wouter Verhelst
On Fri, Aug 29, 2003 at 12:03:34AM +1000, Russell Coker wrote: On Thu, 28 Aug 2003 21:35, Karsten M. Self wrote: Which is a damned good reason for Debian not to package viruses and spam mailers. Or tools which can be readily subverted as such. My Postal program can be used for DOS

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Adam McKenna
On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: #2, Misplaced burden, is the reason for the 'grave' severity. People have a right to ask that unkown people that e-mail them confirm the e-mail. I'm sorry you don't agree with this, but your opinion is hardly justification for a

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Russell Coker
On Fri, 29 Aug 2003 01:32, Wouter Verhelst wrote: I disagree with your conclusions regarding putting viruses in Debian. I think it would be a useful service for people who analyse such things to have copies of viruses in usable form. The EICAR.COM test pattern exists solely for that

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Mark Brown
On Thu, Aug 28, 2003 at 08:21:22AM -0700, Adam McKenna wrote: On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: - TMDA should carry a warning to the user about possible consequences of activating the C-R mechanism, including sending spam, risking Sorry, but no. I will

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Russell Coker
On Thu, 28 Aug 2003 21:35, Karsten M. Self wrote: Which is a damned good reason for Debian not to package viruses and spam mailers. Or tools which can be readily subverted as such. My Postal program can be used for DOS attacks on mail servers, and has been used for such on at least one

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Adam McKenna
On Thu, Aug 28, 2003 at 05:10:07PM +0100, Mark Brown wrote: On Thu, Aug 28, 2003 at 08:21:22AM -0700, Adam McKenna wrote: On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: - TMDA should carry a warning to the user about possible consequences of activating the C-R

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Chad Walstrom
On Thu, Aug 28, 2003 at 12:35:25PM +0100, Karsten M. Self wrote: Thanks to all who've commented on this topic. Interesting reading. Likewise, Karsten. That was a very well written rebuttal to a C-R systems. You followed up with suggetions on using C-R only as a last resort in a mail

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Wouter Verhelst
On Fri, Aug 29, 2003 at 01:42:53AM +1000, Russell Coker wrote: On Fri, 29 Aug 2003 01:32, Wouter Verhelst wrote: I disagree with your conclusions regarding putting viruses in Debian. I think it would be a useful service for people who analyse such things to have copies of viruses in

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Rick Moen
Quoting Adam McKenna ([EMAIL PROTECTED]): I suggest you take these suggestions to the TMDA worker's mailing list at tmda.net, and file wishlist bugs against TMDA for each desired feature. This is an attempt to change the subject: The issue at hand is the cited maintenance (and acceptance)

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Adam McKenna
On Thu, Aug 28, 2003 at 10:27:43AM -0700, Rick Moen wrote: Quoting Adam McKenna ([EMAIL PROTECTED]): I suggest you take these suggestions to the TMDA worker's mailing list at tmda.net, and file wishlist bugs against TMDA for each desired feature. This is an attempt to change the

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Karsten M. Self
on Thu, Aug 28, 2003 at 03:09:48PM +0200, Andreas Metzler ([EMAIL PROTECTED]) wrote: Karsten M. Self kmself@ix.netcom.com wrote: [...] SpamAssassin achieves a false-positive rate (non-spam reported as spam) of 5% with a default threshold of 5. This can be dramatically improved using a

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-28 Thread Karsten M. Self
on Fri, Aug 29, 2003 at 12:03:34AM +1000, Russell Coker ([EMAIL PROTECTED]) wrote: On Thu, 28 Aug 2003 21:35, Karsten M. Self wrote: Which is a damned good reason for Debian not to package viruses and spam mailers. Or tools which can be readily subverted as such. My Postal program can

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Tore Anderson
severity 207300 grave quit * Karsten M. Self Briefly: challenge-response (C-R) spam fighting systems are fundamentally broken by design. I am recommending that TMDA be dropped from Debian. * Adam McKenna I will not respond to this bug other than to state that I don't believe it

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Peter Makholm
Tore Anderson [EMAIL PROTECTED] writes: How many other innocent third parties have you spammed through the use of this broken program? How many of these are Debian users, do you think? I think we could just as well remove postfix[0] on this account. I have received a lot of so called

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Stephen Stafford
[enormous snippage] Sorry, but I do NOT see how this is a grave bug. It's wishlist (at best). YOU might not agree that C-R systems are good (personally I detest them), but that does NOT mean that we shouldn't release one. If the package is in good shape and functions as advertised, then it IS

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Lars Wirzenius
On ke, 2003-08-27 at 13:44, Stephen Stafford wrote: YOU might not agree that C-R systems are good (personally I detest them), but that does NOT mean that we shouldn't release one. If the package is in good shape and functions as advertised, then it IS fit for release. TDMA seems to hurt

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Tore Anderson
[ Please do not send me CC's, as I have not explicitly asked for them. ] * Stephen Stafford Sorry, but I do NOT see how this is a grave bug. It's wishlist (at best). YOU might not agree that C-R systems are good (personally I detest them), but that does NOT mean that we shouldn't

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Colin Watson
severity 207300 wishlist thanks On Wed, Aug 27, 2003 at 11:08:23AM +0200, Tore Anderson wrote: severity 207300 grave quit Sorry, Tore, but this is not a grave bug. The package does what it says on the tin, even if you think that its goals are broken in the wider picture (and I'd happen to

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Mark Brown
On Wed, Aug 27, 2003 at 01:35:12PM +0200, Tore Anderson wrote: with is that the C-R system in question ignores the fact that SMTP headers are trivially (and regulary) forged. I believe this is deliberate, and that TMDA does not attempt to verify that the recipient of the challenge truly

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Tore Anderson
[ Please do not send me CC's, as I have not explicitly asked for them. ] * Tore Anderson How many other innocent third parties have you spammed through the use of this broken program? How many of these are Debian users, do you think? * Peter Makholm I think we could just as well

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Brian May
On Wed, Aug 27, 2003 at 12:58:19PM +0200, Peter Makholm wrote: Tore Anderson [EMAIL PROTECTED] writes: How many other innocent third parties have you spammed through the use of this broken program? How many of these are Debian users, do you think? I think we could just as well

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Bernd Eckenfels
On Wed, Aug 27, 2003 at 02:54:43PM +0300, Lars Wirzenius wrote: TDMA seems to hurt innocent outsiders by sending them mail (e.g., in response to garbage sent by viruses or spammers). The other examples you gave (Emacs, Gnome, CUPS) don't do that, as far as I know. The difference is important,

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Ulrich Eckhardt
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wednesday 27 August 2003 11:08, Tore Anderson wrote: I do not intend to play BTS games here; if you change the severity back to grave, or to any other RC state, I will consider it to be abuse of the BTS and report your actions to the BTS

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Richard Atterer
On Wed, Aug 27, 2003 at 11:08:23AM +0200, Tore Anderson wrote: [snip... oh my!] How amusing to see Sobig.F cited as the reason for reassigning grave severity to a bug! Looks to me as if you just didn't find a sobig-f package to file the bug against, so something else had to be the culprit. In

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Stephen Stafford
On Wed, Aug 27, 2003 at 01:35:12PM +0200, Tore Anderson wrote: [ Please do not send me CC's, as I have not explicitly asked for them. ] Apologies. * Stephen Stafford Sorry, but I do NOT see how this is a grave bug. It's wishlist (at best). YOU might not agree that C-R systems are

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Kalle Kivimaa
Mark Brown [EMAIL PROTECTED] writes: You do realise that all parts of SMTP are generally completely unauthenticated and can be trivially forged? A system like this has no option but to work with unauthenticated data. Why cannot the C-R system issue the challenge during the SMTP session

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread John Goerzen
On Wed, Aug 27, 2003 at 01:43:29PM +0200, Tore Anderson wrote: However, a quick test shows that this is not the case (as Postfix appears to reject the SMTP RCPT command for non-existent accounts), so I fail to see how it is relevant. Sometimes, there is no choice. That could be the case

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Anthony Towns
On Wed, Aug 27, 2003 at 01:43:29PM +0200, Tore Anderson wrote: I fully agree, and I would not hesitate to submit a RC bug on the Postfix That's a completely inappropriate use of the RC severity, and possibly the BTS entirely. The discussion is a good and useful one, trying to inflate your

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Mark Brown
On Wed, Aug 27, 2003 at 04:07:58PM +0300, Kalle Kivimaa wrote: Mark Brown [EMAIL PROTECTED] writes: You do realise that all parts of SMTP are generally completely unauthenticated and can be trivially forged? A system like this has no option but to work with unauthenticated data. Why

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Andreas Metzler
On Wed, Aug 27, 2003 at 10:00:13PM +1000, Brian May wrote: On Wed, Aug 27, 2003 at 12:58:19PM +0200, Peter Makholm wrote: Tore Anderson [EMAIL PROTECTED] writes: How many other innocent third parties have you spammed through the use of this broken program? How many of these are Debian

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Florian Weimer
Bernd Eckenfels [EMAIL PROTECTED] writes: Every MTA is sending bounces to mails with forged headers. The MXes I'm responsible for don't do this (even the secondary MXes handle such cases gracefully). They just refuse messages with unknown destinations at the SMTP level. AFAIK, all MTAs which

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Florian Weimer
Peter Makholm [EMAIL PROTECTED] writes: I think we could just as well remove postfix[0] on this account. I have received a lot of so called bounces because some silly postfix installation believes that I have send mail to some non-existant account. Most MTAs support rejecting unknown

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Wouter Verhelst
On Wed, Aug 27, 2003 at 04:07:58PM +0300, Kalle Kivimaa wrote: Mark Brown [EMAIL PROTECTED] writes: You do realise that all parts of SMTP are generally completely unauthenticated and can be trivially forged? A system like this has no option but to work with unauthenticated data. Why

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Florian Weimer
John Goerzen [EMAIL PROTECTED] writes: Sometimes, there is no choice. That could be the case if, for instance, you are backup MX for a server that is down. You have accepted the message from the original sender already -- possibly hours ago. The primary server comes back up and rejects the

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Brian T. Sniffen
Tore Anderson [EMAIL PROTECTED] writes: severity 207300 grave quit * Karsten M. Self Briefly: challenge-response (C-R) spam fighting systems are fundamentally broken by design. I am recommending that TMDA be dropped from Debian. I use tmda, but not in challenge-response mode. I

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Joey Hess
Stephen Stafford wrote: As long as SOME users like it, and find it useful and it fits THEIR needs, then we should not be removing it from Debian (as long as it meets DFSG). Great! Then someone needs to revive that ITP filed April 1st 2002. This new policy will certianly make a lot of script

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Adam McKenna
On Wed, Aug 27, 2003 at 12:37:36PM +0100, Colin Watson wrote: Perhaps some compromise could be found here to improve the package's description. Adam, I also think it would be helpful if you could respond to at least some points from the original bug report. I do believe that Karsten has

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Florian Weimer
Mark Brown [EMAIL PROTECTED] writes: Why cannot the C-R system issue the challenge during the SMTP session (respond with a reject containing the challenge)? With the latest Sobig flood I've begun to consider all list software sending back The part where SMTP is completely unauthenticated

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Joey Hess
Adam McKenna wrote: The arguments are facile and specious, I do not intend to waste my precious time responding to them. Speaking of precious time, let me bore you with another facile and specious argument.. Like many of us here, I occasionally receive bug reports from our users, and reply for

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Tore Anderson
* Mark Brown You do realise that all parts of SMTP are generally completely unauthenticated and can be trivially forged? Yes. It's indeed very sad that it is so. However, my main issue still remains -- the difference (for the user) between «I'm installing this package and accept

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Kalle Kivimaa
Mark Brown [EMAIL PROTECTED] writes: The part where SMTP is completely unauthenticated means that this doesn't help - the SMTP envelope sender can be forged just as easily as the From: inside the message. You're right, I forgot to say that the idea only applies to non-relayed mail where the

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Mark Brown
On Wed, Aug 27, 2003 at 05:16:40PM +0200, Florian Weimer wrote: Most MTAs support rejecting unknown destinations at the SMTP level. They don't generate bounce messages in such cases. It's a pity if Postfix can't do this. So far, I assumed only qmail had this weird property. Postfix

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Bernhard R. Link
* Florian Weimer [EMAIL PROTECTED] [030827 19:08]: That's why it's better to get rid of generic MX secondaries (IOW secondaries which are not under you administrative control). The effect you describe hampers effective anti-spam measures, too. It can also help anti-spam measures. They are

Re: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Steve Lamb
On Wed, 27 Aug 2003 11:44:34 +0100 Stephen Stafford [EMAIL PROTECTED] wrote: Sorry, but I do NOT see how this is a grave bug. It's wishlist (at best). I tend to agree with the grave aspect. YOU might not agree that C-R systems are good (personally I detest them), but that does NOT mean

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Stephen Gran
This one time, at band camp, Joey Hess said: I don't think that TMDA is yet enough of a problem for this to be a big deal, but I think it has the potential to become one. Debian as a whole is empowered to override the wishes of one maintainer, if it turns out that the software he is

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Colin Watson
On Wed, Aug 27, 2003 at 12:30:07PM -0400, Joey Hess wrote: Adam McKenna wrote: The arguments are facile and specious, I do not intend to waste my precious time responding to them. That's a shame. I don't believe Karsten to be in the habit of putting forward specious arguments. Speaking of

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Branden Robinson
On Wed, Aug 27, 2003 at 12:30:07PM -0400, Joey Hess wrote: Adam McKenna wrote: The arguments are facile and specious, I do not intend to waste my precious time responding to them. Speaking of precious time, let me bore you with another facile and specious argument.. [snip] He's not

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Adam McKenna
On Wed, Aug 27, 2003 at 07:49:27PM +0100, Colin Watson wrote: On Wed, Aug 27, 2003 at 12:30:07PM -0400, Joey Hess wrote: Adam McKenna wrote: The arguments are facile and specious, I do not intend to waste my precious time responding to them. That's a shame. I don't believe Karsten to

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Adam McKenna
On Wed, Aug 27, 2003 at 03:02:33PM -0400, Stephen Gran wrote: I think that either a large warning on bugs.d.o about the use of C-R systems in corrspondence, or a similar warning in the description of TMDA would suffice. I am not familiar with TMDA, so I may be wrong, but couldn't it be

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Gunnar Wolf
Stephen Gran dijo [Wed, Aug 27, 2003 at 03:02:33PM -0400]: The project certainly can and should prohibit maintainers from uploading things that will cause problems for the project (crypto, copyright infringement, etc.), but that is a different case than this. Distributing TMDA doesn't infringe

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Joey Hess
Colin Watson wrote: Some of those challenges arrive at [EMAIL PROTECTED] instead. I'm curious; how many would you say it gets per package on avarage, that have some real impact? (A TMDA response to a BTS ACK mail has little impact.) Perhaps my numbers were low, since I only counted the ones I

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Stephen Gran
This one time, at band camp, Adam McKenna said: Stephen, TMDA does not ship with any defaults, except a couple of customizable text files (templates). It is entirely up to the user to create a TMDA configuration along with his own whitelist and filter directives. TMDA is actually not

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Don Armstrong
On Wed, 27 Aug 2003, Adam McKenna wrote: TMDA does not ship with any defaults, except a couple of customizable text files (templates). It is entirely up to the user to create a TMDA configuration along with his own whitelist and filter directives. If possible, perhaps you could consider

Re: Bug#207300: tmda: Challenge-response is fundamentally broken

2003-08-27 Thread Colin Watson
On Wed, Aug 27, 2003 at 07:26:24PM -0400, Joey Hess wrote: Colin Watson wrote: Some of those challenges arrive at [EMAIL PROTECTED] instead. I'm curious; how many would you say it gets per package on avarage, that have some real impact? (A TMDA response to a BTS ACK mail has little