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RE: Flood of "System Administrator" Undeliverable SPAM, please help

 
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RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 9:41:19 AM   
gilman1

 

Posts: 5
Joined: 21.Feb.2007
Status: offline
Since all outbound e-mails pass GFI too, isn't it possible to keep track of all e-mail addresses to which an e-mail is send last x days. When afterwards, an NDR comes in, GFI can scan if one of these addresses is in the NDR message.
if so => the NDR may be delivered to the user
if not => delete the NDR


I am having the same problem. How do you do this??

(in reply to pmcneill)
Post #: 61
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 10:09:09 AM   
NTAtech

 

Posts: 3
Joined: 20.Sep.2007
Status: offline
Has this issue been resolved yet. My users are being bomborded with NDRs and it seems to be getting worse for us. 100-200 at a time per user. Please assist. The registry change did not work for us. Thanks

(in reply to huffinagle)
Post #: 62
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 11:01:14 AM   
mattbern

 

Posts: 37
Joined: 20.Dec.2006
Status: offline
I've enabled the registry setting

I'm using  zen.spanhaus.org for DNS blacklists  please see  spamhaus.org for rules surronding it's use

I have the latest version of GFI

I also performed the following

http://support.microsoft.com/default.aspx?scid=kb;en-us;886208

and enabled tarpitting

http://support.microsoft.com/kb/842851/en-us

this seems to be pretty successful for me

< Message edited by mattbern -- 7.Apr.2008 11:05:04 AM >

(in reply to NTAtech)
Post #: 63
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 12:30:23 PM   
pmcneill

 

Posts: 132
Joined: 18.May2005
Status: offline
While all of those changes may be good practice, the only one that might possibly have the effect of reducing the amount of backscatter that ends up in your user's mailboxes is the registry change.

I don't see a lot of realistic options for fixing this issue other than the product being able to filter based on a DNSBL that lists known backscatterers. 

(in reply to mattbern)
Post #: 64
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 1:37:16 PM   
caswinans

 

Posts: 59
Joined: 21.Apr.2006
Status: offline
everyone that is experiencing this, do youh HAVE EXTERNAL SPF records?

(in reply to pmcneill)
Post #: 65
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 1:41:01 PM   
pmcneill

 

Posts: 132
Joined: 18.May2005
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We don't.  That could possibly help, but I find it unlikely that a mail server that is misconfigured to send NDRs for addresses not found at their organization would use an SPF lookup to determine that I didn't send them the SPAM they're getting.  Anything is possible though.  What's your experience been?

(in reply to caswinans)
Post #: 66
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 2:43:22 PM   
Eric

 

Posts: 17
Joined: 24.Jul.2007
Status: offline
We have an SPF record, but I guess I don't understand how that would help.  That would just let other servers check to see if an email my domain was sent from the correct IP.  Maybe you can explain what I'm missing.

Eric

(in reply to caswinans)
Post #: 67
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 2:44:42 PM   
caswinans

 

Posts: 59
Joined: 21.Apr.2006
Status: offline
pmcneill

thinking in how GFI works. 

if no SPF is found it passes emails thru at it lowest setting

you state "misconfigured to send NDRs for addresses not found at their organization would use an SPF lookup to " .  if im a spammer and send spam to someone@abc.com and that person doesnt exist @abc.com company if your spf record was correct and they have the mildest settings, the email would fail at SPF and a non deliverable shouldnt be sent


(in reply to pmcneill)
Post #: 68
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 2:48:32 PM   
pmcneill

 

Posts: 132
Joined: 18.May2005
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That's correct, and a good suggestion.  It assumes that a good chunk of the servers that are giving us grief are doing SPF lookups with whatever SPAM solution they are using, but it definitely couldn't hurt, and might stop a chunk of this stuff.

I'm going to look into registering one.  Thanks for a good suggestion!

(in reply to caswinans)
Post #: 69
RE: Flood of "System Administrator" Undeliver... - 7.Apr.2008 5:53:41 PM   
FresnoDoug

 

Posts: 34
Joined: 28.Nov.2007
Status: offline
How about simply checking the autowhitelist against the intended recipient in the NDR? If any of my users had sent the mail that generated the NDR, the intended recipient would be in the autowhitelist. If the recipient isn't in the autowhitelist, wouldn't it be safe to assume the NDR is backscatter & delete it?

(in reply to pmcneill)
Post #: 70
RE: Flood of "System Administrator" Undeliver... - 8.Apr.2008 10:48:35 AM   
pmcneill

 

Posts: 132
Joined: 18.May2005
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quote:

ORIGINAL: FresnoDoug

How about simply checking the autowhitelist against the intended recipient in the NDR? If any of my users had sent the mail that generated the NDR, the intended recipient would be in the autowhitelist. If the recipient isn't in the autowhitelist, wouldn't it be safe to assume the NDR is backscatter & delete it?


Interesting idea. 

(in reply to FresnoDoug)
Post #: 71
RE: Flood of "System Administrator" Undeliver... - 9.Apr.2008 4:48:27 AM   
LukeQuake

 

Posts: 20
Joined: 18.Mar.2008
Status: offline
quote:

ORIGINAL: FresnoDoug

How about simply checking the autowhitelist against the intended recipient in the NDR? If any of my users had sent the mail that generated the NDR, the intended recipient would be in the autowhitelist. If the recipient isn't in the autowhitelist, wouldn't it be safe to assume the NDR is backscatter & delete it?

Good Thinking!

(in reply to FresnoDoug)
Post #: 72
RE: Flood of "System Administrator" Undeliver... - 9.Apr.2008 9:07:15 AM   
pcecom

 

Posts: 16
Joined: 14.Apr.2005
Status: offline
Got hit with another batch of NDR's & DSN's today, over 300 of them. I have applied the registry change, added keywords to GFI and they still seem to get through. This latest batch appears to have a foreign character set in the subject. Looks russian. I remember changing a filter for foreign character sets along time ago so I don't know why these would get through either. We need a fix for this asap!

(in reply to LukeQuake)
Post #: 73
RE: Flood of "System Administrator" Undeliver... - 9.Apr.2008 11:22:44 AM   
JanZoet

 

Posts: 576
Joined: 20.Feb.2008
Status: offline
Hello,

I would like to provide you with an update.

We are still very busy looking into this as per Alexc's post.
Engineering is working on a major change of the MailEssentials Scanning Engine.

We have updated http://kbase.gfi.com/showarticle.asp?id=KBID003322 with a backscatter Blacklist and hopefully you will benefit from using this list.

As soon as I receive another update I will inform you about this via this thread.

Kind regards,

_____________________________

Jan Zoet
Technical Support - GFI Software - www.gfi.com
Messaging, Content Security & Network Security Software

(in reply to pcecom)
Post #: 74
RE: Flood of "System Administrator" Undeliver... - 9.Apr.2008 2:02:44 PM   
FresnoDoug

 

Posts: 34
Joined: 28.Nov.2007
Status: offline
Keep in mind that the backscatter blacklist will be applied to all mail, not just the NDRs.

Also I'm not fond of blacklists www.blacklist.org that require payment to be removed. The one listed in the KB article is in this category.


(in reply to JanZoet)
Post #: 75
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