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Posted to users@spamassassin.apache.org by Rob McEwen <ro...@invaluement.com> on 2020/08/21 19:28:59 UTC

ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one 
for Sendgrid-spams!

...a collection of a new TYPE of DNSBL, with the FIRST of these having a 
focus on Sendgrid-sent spams. AND - there is a FREE version of this - 
that can be used NOW! (/well... might need a SpamAssassin rule or two! 
Your help appreciated!)/:

INFO AND INSTRUCTIONS HERE:

https://www.invaluement.com/serviceproviderdnsbl/

This provides a way to surgically block Sendgrid's WORST spammers, yet 
without the massive collateral damage that would happen if blocking 
Sendgrid domains and IP addresses. But we're NOT stopping at the phishes 
and viruses - and we're not finished! There will be some well-deserved 
economic pain, that puts the recipients' best interests at heart. 
Therefore, flagrant "cold email" spamming to recipients who don't even 
know the sender - is also being targeted - first with the absolute worst 
- and then progressing to other offenders as we make adjustments in the 
coming weeks.

-- Rob McEwen https://www.invaluement.com


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by John Hardin <jh...@impsec.org>.
On Tue, 25 Aug 2020, Rob McEwen wrote:

> On 8/25/2020 11:04 PM, John Hardin wrote:
>> I just wrote something similar to generate a rule, in case for some reason 
>> you don't want to use a plugin. Let me know if there's any interest in it. 
>
> yes - please share!

http://www.impsec.org/~jhardin/antispam/make_sendgrid_rule.sh



-- 
  John Hardin KA7OHZ                    http://www.impsec.org/~jhardin/
  jhardin@impsec.org                         pgpk -a jhardin@impsec.org
  key: 0xB8732E79 -- 2D8C 34F4 6411 F507 136C  AF76 D822 E6E6 B873 2E79
-----------------------------------------------------------------------
   There is no doubt in my mind that millions of lives could have been
   saved if the people were not "brainwashed" about gun ownership and
   had been well armed. ... Gun haters always want to forget the Warsaw
   Ghetto uprising, which is a perfect example of how a ragtag,
   half-starved group of Jews took 10 handguns and made asses out of
   the Nazis.                        -- Theodore Haas, Dachau survivor
-----------------------------------------------------------------------
  2 days until Exercise Your Rights day

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Dominic Raferd <do...@timedicer.co.uk>.
Here's mine, had it running as a regular cron job for a few days now.

On Wed, 26 Aug 2020 at 04:08, Rob McEwen <ro...@invaluement.com> wrote:

> On 8/25/2020 11:04 PM, John Hardin wrote:
> > I just wrote something similar to generate a rule, in case for some
> > reason you don't want to use a plugin. Let me know if there's any
> > interest in it.
>
> yes - please share!
>

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
On 8/25/2020 11:04 PM, John Hardin wrote:
> I just wrote something similar to generate a rule, in case for some 
> reason you don't want to use a plugin. Let me know if there's any 
> interest in it. 

yes - please share!

-- 
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by John Hardin <jh...@impsec.org>.
On Tue, 25 Aug 2020, John Capo wrote:

> Create a file like this from the ids in 
> https://www.invaluement.com/spdata/sendgrid-id-dnsbl.txt
>
> /^bounces\+2191708-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
> account
> /^bounces\+4227563-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
> account
> /^bounces\+13780591-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
> account
> /^bounces\+10163588-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
> account
> /^bounces\+10180020-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
> account
> ...

I just wrote something similar to generate a rule, in case for some reason 
you don't want to use a plugin. Let me know if there's any interest in it.


-- 
  John Hardin KA7OHZ                    http://www.impsec.org/~jhardin/
  jhardin@impsec.org                         pgpk -a jhardin@impsec.org
  key: 0xB8732E79 -- 2D8C 34F4 6411 F507 136C  AF76 D822 E6E6 B873 2E79
-----------------------------------------------------------------------
  Today: the 1941st anniversary of the destruction of Pompeii

Re: ANNOUNCEMENT: The NEW invaluement 'Service Provider DNSBLs' - 1st one for Sendgrid-spams!

Posted by John Capo <jc...@irbs.com>.
On Tue, August 25, 2020 23:07, Rob McEwen wrote:
> Thanks, John Capo, for the suggestions! Honestly, I'm at the end of my rope - completely burned
> out from creating this - desperately needing to catch up in other areas of my business so that I
> can pay my bills. And I have other ideas for how to make this data even better that I'm trying to
> get to asap. So help like this is very appreciated!
>
> BTW - does Postfix "know" to refresh the data when the files are updated? Or is there some kind
> of command that needs to run to tell Postfix to reload the files? How does that work?

Postfix loads regex files when a new smtpd instance is started. Running postfix reload or running postmap on a hashed file forces a restart.

Ideally the ids would be in an RBL so changes are seen in a minute or so.  I pan on adding that capability to my policy server.

> ALSO - would it help if I created a separate set of files for Postfix that are pre-formatted this
> way already?

Dominic Raferd posted a script that does that. Your time is probably better spent elsewhere.

And Paul Stead posted a nice plugin for Spamassassin.

John Capo
Tuffmail.com


>
> Thanks!
>
>
> Rob McEwen, invaluement.com
>
>
>
> On 8/25/2020 2:26 PM, John Capo wrote:
>
>> On 2020-08-25 11:42, Matus UHLAR - fantomas wrote:
>>
>>>
>>> well, do we have anything available now to block at SMTP level? - postfix policy server? -
>>> milter?
>>>
>>>
>>> so far I have noticed only SA plugins. Which is not bad, but that HUGE advantage is not
>>> usable now.
>>
>> Nothing elegant about this but it was easy to implement. You need to create the software
>> specific to your MX servers to update the files below from Rob's web site.
>>
>> Adjust the paths below to your Postfix install
>>
>>
>> Add these entries to your main.cf:
>>
>>
>> smtpd_restriction_classes =    sendgrid
>>
>>
>> # Limit senders that are matched with the regexes in sendgrid-ids # sendgrid =    
>> check_sender_access pcre:/usr/local/etc/postfix/maps/sendgrid-ids
>>
>>
>> smtpd_recipient_restrictions =     check_sender_access
>> hash:/usr/local/etc/postfix/maps/from-sendgrid
>>
>>
>> Create a file like this from the senders in
>> https://www.invaluement.com/spdata/sendgrid-envelopefromdomain-dnsbl.txt
>>
>>
>> sendgrid.net        sendgrid appliedaicourse.com sendgrid bithumbcorp.email   sendgrid
>> bitline.life        sendgrid bureausveritas.com  sendgrid caractere.ro        sendgrid
>> craftsgenerals.com  sendgrid dalvry.com          sendgrid ...
>>
>>
>> Name it from-sendgrid and place it in your Postfix directory postmap from-sendgrid
>>
>> Create a file like this from the ids in
>> https://www.invaluement.com/spdata/sendgrid-id-dnsbl.txt
>>
>>
>> /^bounces\+2191708-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid account
>> /^bounces\+4227563-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid account
>> /^bounces\+13780591-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid account
>> /^bounces\+10163588-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid account
>> /^bounces\+10180020-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid account ...
>>
>>
>> Name it sendgrid-ids and place it in your Postfix directory
>>
>>
>> postfix reload
>>
>> John Capo Tuffmail.com
>>
>>
>
> -- Rob McEwen https://www.invaluement.com +1 (478) 475-9032
>
>
>
>



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
Thanks, John Capo, for the suggestions! Honestly, I'm at the end of my 
rope - completely burned out from creating this - desperately needing to 
catch up in other areas of my business so that I can pay my bills. And I 
have other ideas for how to make this data even better that I'm trying 
to get to asap. So help like this is very appreciated!

BTW - does Postfix "know" to refresh the data when the files are 
updated? Or is there some kind of command that needs to run to tell 
Postfix to reload the files? How does that work? ALSO - would it help if 
I created a separate set of files for Postfix that are pre-formatted 
this way already?

Thanks!

Rob McEwen, invaluement.com


On 8/25/2020 2:26 PM, John Capo wrote:
> On 2020-08-25 11:42, Matus UHLAR - fantomas wrote:
>>
>> well, do we have anything available now to block at SMTP level?
>> - postfix policy server?
>> - milter?
>>
>> so far I have noticed only SA plugins. Which is not bad, but that HUGE
>> advantage is not usable now.
>
> Nothing elegant about this but it was easy to implement. You need to 
> create the software specific to your MX servers to update the files 
> below from Rob's web site.
>
> Adjust the paths below to your Postfix install
>
> Add these entries to your main.cf:
>
> smtpd_restriction_classes =
>    sendgrid
>
> # Limit senders that are matched with the regexes in sendgrid-ids
> #
> sendgrid =
>     check_sender_access pcre:/usr/local/etc/postfix/maps/sendgrid-ids
>
> smtpd_recipient_restrictions =
>     check_sender_access hash:/usr/local/etc/postfix/maps/from-sendgrid
>
> Create a file like this from the senders in 
> https://www.invaluement.com/spdata/sendgrid-envelopefromdomain-dnsbl.txt
>
> sendgrid.net        sendgrid
> appliedaicourse.com sendgrid
> bithumbcorp.email   sendgrid
> bitline.life        sendgrid
> bureausveritas.com  sendgrid
> caractere.ro        sendgrid
> craftsgenerals.com  sendgrid
> dalvry.com          sendgrid
> ...
>
> Name it from-sendgrid and place it in your Postfix directory
> postmap from-sendgrid
>
> Create a file like this from the ids in 
> https://www.invaluement.com/spdata/sendgrid-id-dnsbl.txt
>
> /^bounces\+2191708-[0-9a-f]{4}-/ REJECT Phish from compromised 
> Sendgrid account
> /^bounces\+4227563-[0-9a-f]{4}-/ REJECT Phish from compromised 
> Sendgrid account
> /^bounces\+13780591-[0-9a-f]{4}-/ REJECT Phish from compromised 
> Sendgrid account
> /^bounces\+10163588-[0-9a-f]{4}-/ REJECT Phish from compromised 
> Sendgrid account
> /^bounces\+10180020-[0-9a-f]{4}-/ REJECT Phish from compromised 
> Sendgrid account
> ...
>
> Name it sendgrid-ids and place it in your Postfix directory
>
> postfix reload
>
> John Capo
> Tuffmail.com
>

-- 
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by John Capo <ap...@irbs.com>.
On 2020-08-25 11:42, Matus UHLAR - fantomas wrote:
> 
> well, do we have anything available now to block at SMTP level?
> - postfix policy server?
> - milter?
> 
> so far I have noticed only SA plugins. Which is not bad, but that HUGE
> advantage is not usable now.

Nothing elegant about this but it was easy to implement. You need to 
create the software specific to your MX servers to update the files 
below from Rob's web site.

Adjust the paths below to your Postfix install

Add these entries to your main.cf:

smtpd_restriction_classes =
    sendgrid

# Limit senders that are matched with the regexes in sendgrid-ids
#
sendgrid =
     check_sender_access pcre:/usr/local/etc/postfix/maps/sendgrid-ids

smtpd_recipient_restrictions =
     check_sender_access hash:/usr/local/etc/postfix/maps/from-sendgrid

Create a file like this from the senders in 
https://www.invaluement.com/spdata/sendgrid-envelopefromdomain-dnsbl.txt

sendgrid.net        sendgrid
appliedaicourse.com sendgrid
bithumbcorp.email   sendgrid
bitline.life        sendgrid
bureausveritas.com  sendgrid
caractere.ro        sendgrid
craftsgenerals.com  sendgrid
dalvry.com          sendgrid
...

Name it from-sendgrid and place it in your Postfix directory
postmap from-sendgrid

Create a file like this from the ids in 
https://www.invaluement.com/spdata/sendgrid-id-dnsbl.txt

/^bounces\+2191708-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
account
/^bounces\+4227563-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
account
/^bounces\+13780591-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
account
/^bounces\+10163588-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
account
/^bounces\+10180020-[0-9a-f]{4}-/ REJECT Phish from compromised Sendgrid 
account
...

Name it sendgrid-ids and place it in your Postfix directory

postfix reload

John Capo
Tuffmail.com



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Benny Pedersen <me...@junc.eu>.
Matus UHLAR - fantomas skrev den 2020-08-25 17:42:

> well, do we have anything available now to block at SMTP level?
> - postfix policy server?
> - milter?
> 
> so far I have noticed only SA plugins. Which is not bad, but that HUGE
> advantage is not usable now.

fuglu

i reject highscore spams, just setup fuglu in prequeue with postfix


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Giovanni Bechis <gi...@paclan.it>.
On Tue, Aug 25, 2020 at 08:29:55PM +0200, Benny Pedersen wrote:
> Rob McEwen skrev den 2020-08-25 19:20:
> 
> > PRO TIP: Instead of complaining about this problem on this thread -
> > why not go to the discussion list or forum of your preferred MTA - and
> > ask them to implement it?
> 
> maybe make clamav sigs ?
> 
> is mimedefang working still ?, special plugins needed ?, i just use 
> fuglu
Mimedefang is still alive on a new home:
https://github.com/The-McGrail-Foundation/MIMEDefang
I think it should not be complicated to implement it.
  Giovanni 

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
On 8/25/2020 2:29 PM, Benny Pedersen wrote:
> maybe make clamav sigs ? 


Benny,

Thanks for your other suggestions - those are worth exploring.

Also - the Clamav Sigs is not a bad idea - but even besides the fact 
that (like SA rules), Clamav is content filtering and not at the 
SMTP-Envelope level - Clamav doesn't tend to have nearly AS fast of a 
turnaround time as do DNSBLs.

In a previous message, someone was disappointed that we missed one, and 
it turns out our 24-second turnaround time on that message (from the 
start of the SMTP connection - to being fully deployed in the data) was 
a contributing factor. We now have a plan to shorten that 24-seconds to 
about 4 seconds AND (for invaluement subscribers) - we have a "push" 
technology that is available now where those invaluement subscribers who 
opt for this feature (no extra charge!) - can get a split second 
notification to run their RSYNC just 1 second after the file updates - 
and we do that already for our direct query servers. So there is an 
option (once implemented!) to potentially get the these FULLY 
DISTRIBUTED within about 8 seconds from the start of the SMTP connection 
of the first such spam received - to being FULLY deployed on DNS servers 
(both our own direct query servers - and our RSYNC subscribers' internal 
rbldnsd servers) - that will be AMAZING. I expect to be there within a 
week from now. Something like clamav just can't even begin to compete 
with that fast of a turnaround. But ClamAv rules may still be a good way 
to get this implemented for many.

Someone else mentioned one that was completely off of our radar - but 
we're about to double the coverage of these in terms of mailboxes and 
traps used for this purpose - so that will help further minimize our 
"blind spots".

-- 
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Benny Pedersen <me...@junc.eu>.
Rob McEwen skrev den 2020-08-25 19:20:

> PRO TIP: Instead of complaining about this problem on this thread -
> why not go to the discussion list or forum of your preferred MTA - and
> ask them to implement it?

maybe make clamav sigs ?

is mimedefang working still ?, special plugins needed ?, i just use 
fuglu


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
On 8/25/2020 1:20 PM, Rob McEwen wrote:
> but I can do everything, at least not all at once

*can't do

-- 
Rob McEwen
https://www.invaluement.com
  


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
On 8/25/2020 11:42 AM, Matus UHLAR - fantomas wrote:
> well, do we have anything available now to block at SMTP level?
> - postfix policy server?
> - milter?
> so far I have noticed only SA plugins. Which is not bad, but that HUGE
> advantage is not usable now. 


And likewise - 48 hours ago - a SpamAssassin plugin didn't exist either! 
These things take at least a little bit of time. We're only at the 3rd 
business day that this tech has been in existence. But I think you and I 
would both be surprised at how many systems are likely already (quietly) 
using this at the SMTP-connection level, for certain more 
custom-programmed systems. I believe adaptation in other public MTAs is 
inevitable. For example, I have some good contacts at Exim and it's on 
my "to do" list to ask them about this, but I can do everything, at 
least not all at once. And those MTAs that don't enable usage of this 
will be left behind.

PRO TIP: Instead of complaining about this problem on this thread - why 
not go to the discussion list or forum of your preferred MTA - and ask 
them to implement it?

-- 
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
>>--On Saturday, August 22, 2020 11:15 AM -0400 Jered Floyd 
>><je...@convivian.com> wrote:
>>>Like most ISPs, they have a feedback loop to remove malicious users.  I
>>>assume it is too slow, so a SendGrid account ID RBL would provide
>>>meaningful value.

>On 8/22/2020 3:35 PM, Kenneth Porter wrote:
>>Would not Pyzor accomplish the same thing? Submit the SendGrid spam 
>>to Pyzor to quickly get it blacklisted.

On 22.08.20 17:23, Rob McEwen wrote:
>sendgrid list can do the filtering at the SMTP-envelope level - BEFORE 
>the message is even downloaded - for some systems with millions of 
>users - that is a HUGE advantage.
>
>(2) being filterable at the SMTP-Envelope level opens up possibilities 
>for things like MTA plugins or feature additions - that enable this 
>filtering at the MTA level - for MTAs that do NOT try to do any 
>content filtering of the message. That creates more options for 
>deployment where many will hopefully be able to make use of this, who 
>don't have Pyzor (for whatever reasons)

well, do we have anything available now to block at SMTP level?
- postfix policy server?
- milter?

so far I have noticed only SA plugins. Which is not bad, but that HUGE
advantage is not usable now.


-- 
Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
I drive way too fast to worry about cholesterol.

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Rob McEwen <ro...@invaluement.com>.
On 8/22/2020 3:35 PM, Kenneth Porter wrote:
> --On Saturday, August 22, 2020 11:15 AM -0400 Jered Floyd 
> <je...@convivian.com> wrote:
>
>> Like most ISPs, they have a feedback loop to remove malicious users.  I
>> assume it is too slow, so a SendGrid account ID RBL would provide
>> meaningful value.
>
> Would not Pyzor accomplish the same thing? Submit the SendGrid spam to 
> Pyzor to quickly get it blacklisted.


(1) Pyzor requires resource-expensive content filtering - whereas the 
sendgrid list can do the filtering at the SMTP-envelope level - BEFORE 
the message is even downloaded - for some systems with millions of users 
- that is a HUGE advantage.

(2) being filterable at the SMTP-Envelope level opens up possibilities 
for things like MTA plugins or feature additions - that enable this 
filtering at the MTA level - for MTAs that do NOT try to do any content 
filtering of the message. That creates more options for deployment where 
many will hopefully be able to make use of this, who don't have Pyzor 
(for whatever reasons)

(3) The strategy you described is SOMETIMES easily defeated with certain 
variations in the messages, where each message is sufficiently different 
to NOT be blockable by Pyzor. That is a HUGE loophole in Pyzor 
technology. This Sendgrid ID list doesn't have that problem.

(4) Also, a spammer who sends out many different types of spams - can 
potentially stay off of Pyzor's radar - but yet ALL of those spams under 
that Sendgrid ID - will be collectively noticed in our engine. And, 
likewise, Pyzor's methods could create a game of whack-a-mole. The 
spammer will just keep coming out with new types of spam - that all get 
past Pyzor while Pyzor tries to catch up - then Pyzor catches up - then 
the spammer just reformats the content. Rinse. Repeat. Meanwhile, ALL of 
those LATER spams are ALREADY blocked by our Sendgrid list BEFORE the 
next types of spams are sent - ALL OF THEM. (you could argue that we 
might get into a game of whack-a-mole too with those Sendgrid IDs - but 
we're FAR less vulnerable to that - it will happen MUCH LESS often!)

(5) for these reasons and others - I strongly suspect that our Sendgrid 
list is going to have a MUCH faster turnaround time on listing the 
initial spams from a new sendgrid ID - and, as mentioned, their later 
spams will then ALREADY be caught by this Sendgrid list - while Pyzor is 
bogged down in that silly whack-a-mole game.

Don't get me wrong - Pyzor and other such checksum content filters - are 
wonderful and have their place - but thinking that they remove the need 
for this Sendgrid list - is absolutely not even close to true.

-- 
Rob McEwen
https://www.invaluement.com
+1 (478) 475-9032



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Jered Floyd <je...@convivian.com>.

----- On Aug 22, 2020, at 3:35 PM, Kenneth Porter shiva@sewingwitch.com wrote:

>> Like most ISPs, they have a feedback loop to remove malicious users.  I
>> assume it is too slow, so a SendGrid account ID RBL would provide
>> meaningful value.
> 
> Would not Pyzor accomplish the same thing? Submit the SendGrid spam to
> Pyzor to quickly get it blacklisted.

SA has multiple overlapping metrics.  As long as they are not fully overlapping, each adds to spam/ham assurance.

As Rob points out, it's also valuable to prioritize low-cost tests on inbound mail -- matching a sender ID is simpler than a message digest.

--Jered

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Kenneth Porter <sh...@sewingwitch.com>.
--On Saturday, August 22, 2020 11:15 AM -0400 Jered Floyd 
<je...@convivian.com> wrote:

> Like most ISPs, they have a feedback loop to remove malicious users.  I
> assume it is too slow, so a SendGrid account ID RBL would provide
> meaningful value.

Would not Pyzor accomplish the same thing? Submit the SendGrid spam to 
Pyzor to quickly get it blacklisted.




Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Jered Floyd <je...@convivian.com>.

----- On Aug 21, 2020, at 10:37 PM, Philip Prindeville philipp_subx@redfish-solutions.com wrote:

> I fail to see the point: that we do the work that sendgrid should be doing, but
> on a duplicative scale?
> 
> Why don’t they police themselves?

Presumably for the same reasons we filter spam at all.  SendGrid is a (type of) ISP.  Users sign up, and create and send content.  Some of that content is spam.  We want to block the spam, without blocking the entire ISP.

Like most ISPs, they have a feedback loop to remove malicious users.  I assume it is too slow, so a SendGrid account ID RBL would provide meaningful value.

(The easiest way to consume this is surely as an DNS RBL?)

--Jered

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Axb <ax...@gmail.com>.
On 8/22/20 4:37 AM, Philip Prindeville wrote:
> 
> 
>> On Aug 21, 2020, at 1:28 PM, Rob McEwen <ro...@invaluement.com> wrote:
>>
>> ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!
>>
>> ...a collection of a new TYPE of DNSBL, with the FIRST of these having a focus on Sendgrid-sent spams. AND - there is a FREE version of this - that can be used NOW! (well... might need a SpamAssassin rule or two! Your help appreciated!):
>>
>> INFO AND INSTRUCTIONS HERE:
>>
>> https://www.invaluement.com/serviceproviderdnsbl/
>>
>> This provides a way to surgically block Sendgrid's WORST spammers, yet without the massive collateral damage that would happen if blocking Sendgrid domains and IP addresses. But we're NOT stopping at the phishes and viruses - and we're not finished! There will be some well-deserved economic pain, that puts the recipients' best interests at heart. Therefore, flagrant "cold email" spamming to recipients who don't even know the sender - is also being targeted - first with the absolute worst - and then progressing to other offenders as we make adjustments in the coming weeks.
>>
> 
> 
> I fail to see the point: that we do the work that sendgrid should be doing, but on a duplicative scale?
> 
> Why don’t they police themselves?
> 
> We’re effectively calling out spam that’s escaped after the fact.  What’s the point of that?
> 
> They should be scanning email as it leaves their infrastructure and using rules and Bayesian filters to know if something is amiss and they need to have human intervention.
> 
> Nothing is stopping them from doing the right thing.
> 
> Why should we enable their bad behavior?
>

The point is to prevent Phish, Spearphish and other bad stuff, not just 
"spam"

seems you're sort of late to the party...
Get on board @ Mailop, SDLU, etc lists



Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Philip Prindeville <ph...@redfish-solutions.com>.

> On Aug 21, 2020, at 1:28 PM, Rob McEwen <ro...@invaluement.com> wrote:
> 
> ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!
> 
> ...a collection of a new TYPE of DNSBL, with the FIRST of these having a focus on Sendgrid-sent spams. AND - there is a FREE version of this - that can be used NOW! (well... might need a SpamAssassin rule or two! Your help appreciated!):
> 
> INFO AND INSTRUCTIONS HERE:
> 
> https://www.invaluement.com/serviceproviderdnsbl/
> 
> This provides a way to surgically block Sendgrid's WORST spammers, yet without the massive collateral damage that would happen if blocking Sendgrid domains and IP addresses. But we're NOT stopping at the phishes and viruses - and we're not finished! There will be some well-deserved economic pain, that puts the recipients' best interests at heart. Therefore, flagrant "cold email" spamming to recipients who don't even know the sender - is also being targeted - first with the absolute worst - and then progressing to other offenders as we make adjustments in the coming weeks.
> 


I fail to see the point: that we do the work that sendgrid should be doing, but on a duplicative scale?

Why don’t they police themselves?

We’re effectively calling out spam that’s escaped after the fact.  What’s the point of that?

They should be scanning email as it leaves their infrastructure and using rules and Bayesian filters to know if something is amiss and they need to have human intervention.

Nothing is stopping them from doing the right thing.

Why should we enable their bad behavior?


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Paul Stead <pa...@gmail.com>.
The following plugin extracts the SendGrid ID to a Tag, now we can use it
with askdns..

https://github.com/fmbla/spamassassin-sendgrid

Paul


On Sun, 23 Aug 2020 at 20:42, Giovanni Bechis <gb...@apache.org> wrote:

> On 8/21/20 9:28 PM, Rob McEwen wrote:
> > ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one
> for Sendgrid-spams!
> >
> > ...a collection of a new TYPE of DNSBL, with the FIRST of these having a
> focus on Sendgrid-sent spams. AND - there is a FREE version of this - that
> can be used NOW! (/well... might need a SpamAssassin rule or two! Your help
> appreciated!)/:
> >
> SpamAssassin plugin available at:
> https://github.com/bigio/spamassassin-esp/archive/esp-v0.1.tar.gz
>
> We will work on improving this new type of DNSBL with more data and more
> features, stay tuned.
>
>  Giovanni
>
> > INFO AND INSTRUCTIONS HERE:
> >
> > https://www.invaluement.com/serviceproviderdnsbl/
> >
> > This provides a way to surgically block Sendgrid's WORST spammers, yet
> without the massive collateral damage that would happen if blocking
> Sendgrid domains and IP addresses. But we're NOT stopping at the phishes
> and viruses - and we're not finished! There will be some well-deserved
> economic pain, that puts the recipients' best interests at heart.
> Therefore, flagrant "cold email" spamming to recipients who don't even know
> the sender - is also being targeted - first with the absolute worst - and
> then progressing to other offenders as we make adjustments in the coming
> weeks.
> >
> > -- Rob McEwen https://www.invaluement.com
> >
>
>

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Giovanni Bechis <gb...@apache.org>.
On 8/21/20 9:28 PM, Rob McEwen wrote:
> ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!
> 
> ...a collection of a new TYPE of DNSBL, with the FIRST of these having a focus on Sendgrid-sent spams. AND - there is a FREE version of this - that can be used NOW! (/well... might need a SpamAssassin rule or two! Your help appreciated!)/:
> 
SpamAssassin plugin available at:
https://github.com/bigio/spamassassin-esp/archive/esp-v0.1.tar.gz

We will work on improving this new type of DNSBL with more data and more features, stay tuned.

 Giovanni

> INFO AND INSTRUCTIONS HERE:
> 
> https://www.invaluement.com/serviceproviderdnsbl/
> 
> This provides a way to surgically block Sendgrid's WORST spammers, yet without the massive collateral damage that would happen if blocking Sendgrid domains and IP addresses. But we're NOT stopping at the phishes and viruses - and we're not finished! There will be some well-deserved economic pain, that puts the recipients' best interests at heart. Therefore, flagrant "cold email" spamming to recipients who don't even know the sender - is also being targeted - first with the absolute worst - and then progressing to other offenders as we make adjustments in the coming weeks.
> 
> -- Rob McEwen https://www.invaluement.com
> 


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by RW <rw...@googlemail.com>.
On Fri, 28 Aug 2020 15:21:53 +0100
RW wrote:
 
> " WHERE ARE THE DATA FILES?
> 
>   For all of these, right click , then 'save as' - then later you can
>   set them up for frequent downloads (every minute!) using CURL or
> WGET

If anyone's using FreeBSD it's best to avoid fetch -m.

fetch doesn't consider the file unmodified unless the sizes also match,
and the server isn't providing the file size. 


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by RW <rw...@googlemail.com>.
On Fri, 28 Aug 2020 08:10:17 -0500
bwalton+1576874476@leepfrog.com wrote:

> Thanks Rob!
> 
> I've done an initial download of the data files and will use, as
> requested, wget's timestamping flag.  How, often do you expect these
> files to be updated?  Just trying to determine how often to check for
> updates.
> 
> Thanks,
> Bryan


" WHERE ARE THE DATA FILES?

  For all of these, right click , then 'save as' - then later you can
  set them up for frequent downloads (every minute!) using CURL or WGET
  - only using the setting that only downloads when the server versions
  are newer. "


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by bw...@leepfrog.com.
Thanks Rob!

I've done an initial download of the data files and will use, as
requested, wget's timestamping flag.  How, often do you expect these
files to be updated?  Just trying to determine how often to check for
updates.

Thanks,
Bryan

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Benoit Panizzon <be...@imp.ch>.
Hi Rob

This works like a charm, blocking a lot of: bounces+8465718 atm.

Thank you for your excellent plugin!

Mit freundlichen Grüssen

-Benoît Panizzon-
-- 
I m p r o W a r e   A G    -    Leiter Commerce Kunden
______________________________________________________

Zurlindenstrasse 29             Tel  +41 61 826 93 00
CH-4133 Pratteln                Fax  +41 61 826 93 01
Schweiz                         Web  http://www.imp.ch
______________________________________________________

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by "M. Omer GOLGELI" <om...@chronos.com.tr>.
Sendgrid and their likes...

Checking 1 days logs for 1 domain, I see that of the 17 SendGrid mails to hit my antispam gateway, 17 of them were spam from 9 distinct senders.

I can't deal with hunting spammers like that, giving a nice little score the spam tools that allow this kind of mass mailing without checks is the better approach IMO. 





M. Omer GOLGELI


August 22, 2020 10:17 AM, "Benny Pedersen" <me...@junc.eu> wrote:

> @lbutlr skrev den 2020-08-22 08:03:
> 
>> On 21 Aug 2020, at 14:15, Benny Pedersen <me...@junc.eu> wrote:
>>> blacklist_from *+14927644-*
>> 
>> I think adding 5.0 to all sendgrid mail is the best idea I've heard.
>> Sendgrid makes me long for the days of the SPEWS RBL.
> 
> i am soon to be tired of it to add it to rpz in bind9

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Benny Pedersen <me...@junc.eu>.
@lbutlr skrev den 2020-08-22 08:03:
> On 21 Aug 2020, at 14:15, Benny Pedersen <me...@junc.eu> wrote:
>> blacklist_from *+14927644-*
> 
> I think adding 5.0 to all sendgrid mail is the best idea I've heard.
> 
> Sendgrid makes me long for the days of the SPEWS RBL.

i am soon to be tired of it to add it to rpz in bind9

Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by "@lbutlr" <kr...@kreme.com>.
On 21 Aug 2020, at 14:15, Benny Pedersen <me...@junc.eu> wrote:
> blacklist_from *+14927644-*

I think adding 5.0 to all sendgrid mail is the best idea I've heard.

Sendgrid makes me long for the days of the SPEWS RBL.


-- 
These are the thoughts that kept me out of the really good schools.
	-- George Carlin


Re: ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one for Sendgrid-spams!

Posted by Benny Pedersen <me...@junc.eu>.
Rob McEwen skrev den 2020-08-21 21:28:
> ANNOUNCEMENT: The NEW invaluement "Service Provider DNSBLs" - 1st one
> for Sendgrid-spams!

(1) Sendgrid IDs that are found OFTEN in the SMTP-ENVELOPE FROM address 
of Sendgrid-sent messages.
EXAMPLE: <bo...@sendgrid.net>
So this THIS case, 14927644 is the ID. Nothing more. Nothing less.

blacklist_from *+14927644-*

untested but should work

i just use this form

blacklist_from *-rob=pvsys.com@sendgrid.net

:-)