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SORBS - Is There a Better Spam Blacklist?

rootnl asks: "Recently I decided to upgrade my email server with better spam detection and decided to use the SORBS blacklist. It is a very aggressive blacklist and could be deemed quite effective. However, I discovered two totally legal servers currently being blocked by their Spam 'o Matic service: a Google Gmail server (64.233.182.185), and another server belonging to an ISP called Orange (193.252.22.249). Now, normally one would think these providers would probably get themselves de-listed, but the process provided revolves around donating money. As I just happen to have a friend that is using the said ISP, I have to seriously reconsider using SORBS. What is your experience with SORBS? If you have alternatives, what would you suggest as a better blacklist service?"

35 of 226 comments (clear)

  1. Dunno about better by melonman · · Score: 5, Informative

    But avoid SPEWS like the plague. They have a wonderful policy of blacklisting entire 16-bit IP ranges because one machine in an enormous server park has been used to send spam.

    They know this causes massive collateral damage to machines administrated by totally independent companies, many of them small and liable to suffer severe hardship because of this arbitrary action. That's precisely the idea: they keep hurting non-spammers to make them lobby the server parks to deal with the spammers.

    Unless you think that kidnapping children and refusing to return them unless their parents fight the mafia for you is an ethical law-enforcement policy, SPEWS is obviously far far worse than the problem they are allegedly attempting to solve.

    --
    Virtually serving coffee
    1. Re:Dunno about better by Brightest+Light · · Score: 3, Insightful

      What exactly is an RBL operator supposed to do about large server parks that simply do not give a shit about the spammers residing on their network? What do you do about networks that actively aid spammers by moving them around and around to clean IP space as they're blacklisted? Playing IP whack-a-spammer went out of fashion years ago, and obviously asking politely doesn't work. Yeah, finding your ISP listed on SPEWS sucks, because there's no real way to contact them; though you can beg in NANAE and NANABL for the entertainment of the wannabe 'spam-fighters' till you're blue in the face -- but if your ISP does not care about the fact that one of their customers is stealing bandwidth, CPU cycles, and time from other people and their ISPs, what else can SPEWS do about it? My understanding of the SPEWS escalation process is that they notify the ISP about the spammer on their network, and then if nothing is done, they list the surrounding IP blocks in an ever-increasing fashion. Meaning if the ISP simply does not care that there's a spammer on their network, they are made to care by virtue of their entire netspace being (eventually) listed. What else *can* an RBL operator do when the ISP does not listen or care? I ask this as a serious question. IANASFBFNANAE (I am not a SPEWS fan boy from NANAE) - in fact, I don't directly use RBLs any longer.

    2. Re:Dunno about better by Lost+Race · · Score: 3, Informative

      SPEWS is probably not relevant any more. There have been no changes to the published DNSBL zones since 2006-08-24; apparently the database is no longer being maintained.

    3. Re:Dunno about better by meringuoid · · Score: 2, Insightful
      The error in your reasoning starts when you assume that self-appointed do-gooders have the right to infringe the rights of third parties.

      Is it the right of the owner of a mail server freely to accept or refuse messages at will? Is it his right to define whatever rules he wishes for the acceptance or rejection of email? Is there anybody in the world who has the right to order him to do otherwise?

      If the answers are 'yes', 'yes' and 'no' respectively, I submit to you that it is those who would silence SORBS, SPEWS and the like who are infringing the rights of third parties, by ordering mail admins to only use means of filtering email of which they personally approve.

      --
      Real Daleks don't climb stairs - they level the building.
    4. Re:Dunno about better by mvdwege · · Score: 2, Informative
      If SPEWS feel the need to punish ISPs for their behaviour, they need two classes of blacklist: [...]

      People would take you a lot more seriously if you would do your homework before making bold statements.

      Hint: try reading the SPEWS FAQ and looking at the database before spouting off.

      Mart
      --
      "I know I will be modded down for this": where's the option '-1, Asking for it'?
  2. SURBL by tootired · · Score: 5, Informative

    SURBL is a URL blacklist.

    Employing it enables your spam software to block emails that have matching blocked urls in the message body.

    I have not gotten any false positives with it and it blocks a ton of nasty phishing stuff in addition to the usual SpermaMAXX crap.

  3. Expect many false positives by dtfinch · · Score: 3, Informative

    All the blacklists I know have a tendency to block entire ISPs rather than just the ranges known to generate spam, if they think the ISP isn't taking sufficient action against its spammers or spambot infected customers.
    Blacklists and whitelists are useful, but I wouldn't use them as the sole indicator of whether or not an email is spam.

    1. Re:Expect many false positives by mutterc · · Score: 2, Informative

      Spamhaus claims to not do this... the only time they list IPs that are not spam sources are pre-emptively when a spammer on their ROKSO list gets an account, and sometimes ISP's corporate mail servers (not the customers' ones, and not customer machines).

  4. SORBS should be shut down. by finchwizard · · Score: 5, Interesting

    I'm sorry but SORBS should be shut down. The amount of time I myself and many colleagues have managed to get onto SOBS because we were classed as a dynamic IP range, despite having blocks of IP's and it's extremely hard to get off it. I understand blocking people with Open relay servers, but being in a dynamic range, which can mean IP's being assigned to you from your ISP is a joke. Everyone should be boycotting these guys, two of the large ISP's in Australia use these guys to filter out spam, and are being blocked by small business's and Education. I've never posted comments on Slashdot yet, but this is one I feel very strongly on, and SORBS should be avoided at all costs. If they deem you a Spammer, despite proving to them you are not, they still reserve the right to keep you on the list and completely screw over your business.

    1. Re:SORBS should be shut down. by CowboyBob500 · · Score: 2, Interesting

      I use SORBS precisely because they block dynamic IP ranges. 99% of spam comes from trojaned machines on dynamic IPs and I find this extremely effective at blocking spam. If your mailserver lives on a dynamically assigned IP then that is your problem. In my opinion a mail server should ALWAYS be on a static IP - I view it as a sign of a trusted mail server. If your ISP can't provide this, then you need to change your ISP. I'm sorry, but I have absolutely no sympathy in this situation. There is no reason for a real business to rely on dynamic IPs on their servers.

      Bob

    2. Re:SORBS should be shut down. by finchwizard · · Score: 4, Insightful

      All 30 IP's I rent are Static, and that has never changed over the years I've owned them, my servers are also running Linux and are very secure with both Spamassassin and ClamAV scanning, as well as blocking certain mimetypes. So don't give me dynamic IP range stuff, I was lucky that my ISP managed to straighten them out, but I've had friends that aren't as lucky. Of course SORBS is going to block a high rate of spam, it's also blocking a lot of legitimate people, and the fact they are extorting people to get off the list is ludacris.

  5. Orange = Wanadoo by grahamm · · Score: 4, Informative

    Orange is part of Wanadoo who are known to be both spam friendly and to host spamvertised web sites. So maybe listing Orange is not such a bad idea.

    1. Re:Orange = Wanadoo by Ksempac · · Score: 3, Informative

      First Wanadoo doesnt exist anymore. Second Orange has never been part of Wanadoo. Wanadoo was the ISP branch of France Telecom (the main phone company in France), who bought the British mobile phone company Orange. Then they decided to merge all their mobile phones/ISP services in Europe (including Wanadoo and Orange, but also many others) into one single company called Orange. Third, before saying some company is spam friendly, you should get some reliable source.

    2. Re:Orange = Wanadoo by grahamm · · Score: 2, Informative

      If you do a 'whois' search on the IP address given for the 'Orange' ISP it shows the owner as being Wanadoo Netherlands.

  6. it's not the providers job to delist themself by tolonuga · · Score: 2, Insightful

    if you run a anti spam filter, it is your job to make sure your data is accurate.
    but if you think your users would pressure some admin so they get back to you,
    that is keeping mails hostage and not an acceptable practice.

    if you do that, it is not part of the solution, it is part of the problem.

  7. Use spam assassin with more that one RBL by simm1701 · · Score: 3, Insightful

    I prefer to use spam assassin and use a couple of RBLs with various weightings on each.

    I keep the weightings quite low since I find most of the RBLs too agressive - added to the bayes and other checks however it is quite good at pushing spam into the right destination (and for the very spammy thats /dev/null)

    True this means I actually have to receive and process the mail rather than just arbitarily ignoring connections, but my mail server doesn't really get that much traffic as its only personal use.

    --
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    1. Re:Use spam assassin with more that one RBL by Zocalo · · Score: 4, Informative

      To extend on that I also have a META rule set up to handle DNSBLs in SpamAssassin that adds some additional points based on how many RBLs each IP address has hit. A server on one DNSBL may be a false positive or an over aggressive listing, but if it's on three or four then it's almost certainly spam and gets an extra couple of points towards being classed as spam. If it matches five or more, then it gets an instant +50 file in the mailbox "/dev/null" score.

      --
      UNIX? They're not even circumcised! Savages!
  8. Freedom2Surf by Phil+John · · Score: 3, Interesting

    They're currently allegedly trying to extort money from a UK ISP Freedom2Surf (sadly now part of the Pipex group).

    By default SORBS apparently block all dynamic IP's. For some strange reason they've deemed that 8192 IP's that are actually in the F2S static range are dynamic because the reverse DNS includes the IP address.

    I've heard that they want $50 per IP to unblock them. They wont even talk to users who have static IP address in that range to get the block lifted.

    --
    I am NaN
  9. SORBS should be avoided at all costs by Anonymous Coward · · Score: 4, Informative

    Several reasons why:
    Large netblocks will be repeatedly put onto one of their lists if they dont comply with the founder/main admin's idea of how reverse dns should be configured. They will list IP blocks that dont conform to an RFC that funnily enough, he wrote.

    Getting in contact with them in any reasonable timeframe is damn near impossible in any timely manner.
    Primary/Secondary SMTP servers of ISP's will often by listed as part of their blanket block approach.

    They continually block whole IP ranges that are statically assigned, often automatically with seemingly no human oversight. There can be found many complaints on assorted web forums across the net, especially australian, full of people trying to figure out why they were listed on one of the sorbs lists, and how to be removed.

    Almost all of the issues i have run into with SORBS dont seem to have anything to do with eliminating spam, more to do with pushing the founders RFC for reverse lookups. Comply, and you are free from hassle forever. Fail to comply, and face loosing SMTP access to any providers using SORBS for anythere from a day to over a week.

  10. SORBS!!! I'd like to ABsorb the so-and-so's!!! by Anonymous Coward · · Score: 5, Interesting

    I have a fixed IP address provided by my ISP. I run my own servers and have done for nearly 10 years. My servers are not now, and have never been Open Relay. I have run every possible test to make sure that is the case. SORBS, in their infinite wisdom, deem my address to be dynamic because it is part of a permanently leased dynamic range, so they block me, and therefore I cannot send email to anyone using two of the major ISP's in Australia. I have emailed sorbs and asked them to check my server. No response. I have spoken to the Telecommunications Industry Ombudsman in Australia, who tell me they can't do anything, that I should talk to "The Australian Communications and Media Authority", but if you are to check the SORBS site it specifically mentions that "The Australian Communications and Media Authority" have no influence over them at all. I have threatened SORBS with legal action. No response. Basically, they don't care less that I can't send email to the majority of Australia's internet users, because I won't donate money to them.

    If you visit their site their tag line says "Fighting spam by finding and listing Exploitable Servers." This really should read "Exploiting small businesses through a cash for delisting scam".

    Oh, and I forgot to mention, I've been told that the two major Australian ISP's who use SORBS just happen to form part of the "group of companies as a private venture" that make up SORBS. Interesting huh?

  11. SpamHaus, SPEWS and SpamCop by christophe.vg · · Score: 4, Informative

    For a few years now, I'm using three RBL's to filter the incoming mails on our mail server, which hosts a few small-sized customers and some personal domains. The RBL's I use are: SpamHaus, SPEWS and SpamCop. We have set them up in sequence, so that a mail caught by one is not passed to the following anymore.

    Looking at two days ...

    01/01/07
    total mails processed : 1432
    considered non-spam : 719 (50.21%)
    total number of blocks : 713 (49.79%)
    spamhaus : 630 (88.36%)
    spews : 2 ( 0.28%)
    spamcop : 81 (11.36%)

    01/01/06
    total mails processed : 381
    considered non-spam : 155 (40.68%)
    total number of blocks : 226 (59.32%)
    spamhaus : 191 (84.51%)
    spews : 31 (13.72%)
    spamcop : 4 ( 1.77%)

    ... it shows the trend I've seen over this time: SpamHaus does a great job for me and we haven't received any complaints from the customers concerning people not able to contact them.

    Given these (poor-man's statistics) it seems that SPEWS is of little use to us. SpamHaus catches most of the problems. Maybe even if we switched SPEWS' and SpamCop's order, we might see that the latter would be able to catch those mails now caught by the former. It's surely something we're going to try.

    On the other hand, it might very well be that SPEWS would catch also all SPAM caught by SpamHaus. Reversing the current order might be a nice test before we come to any real conclusions on which RBL to drop ;-)

    The (current) bottom line: For us, SPEWS isn't causing any problems, but also doesn't help us that much. SpamHaus seems to be a great RBL source and SpamCop seems to be a nice addition.

    But it doesn't stop all SPAM.

  12. SORBS? by sigmoid_balance · · Score: 2, Insightful

    Orange is not just an ISP. It's a multinational mobile telecom company. http://en.wikipedia.org/wiki/Orange_SA. As far as I know, after they were bought by France Telecom, they moved many their servers to a unique class B adress space. Maybe that address you found is from the old ones, which is not used anymore for mail, so unblocking it doesn't interest them.

    On the other hand, getting a blacklist like this, doesn't seem to solve your problem: getting less SPAM. Do you think spammers don't have enough money to get themselves out of blacklists? Do you think that every individual legit(not SPAM) business or server checks all, of the many, blacklists to see if he's on one of them? And if they do, how many will pay the fee to get themselves of that list?

  13. sbl-xbl by Halo1 · · Score: 4, Informative

    sbl contains the spamhauses, xbl trojaned boxes/open proxies etc (you can of course also only use one of them). See http://www.spamhaus.org/xbl/index.lasso

    --
    Donate free food here
  14. sorbs is one the best blacklists out there by cyberfoxz · · Score: 3, Informative

    I work at the abuse dept. of a large dutch ISP and we rely heavily on sorbs. When I started working there one of my collegues convinced us that there is no way you could be able to contact sorbs and I thought that to be true. We found out however that it is really not that hard to get in touch with them and if you follow their guidlines, you never have to pay for delisting. The paying part is mainly to scare of spammers delisting adresses they do not own. They use a smal set of totaly acceptable rules to delist adresses from their DUL list (if u use a mailserver on a dynamic adres, go get a static one. If you can't, you should be using your ISP's mailserver). Their rules:
    1. Only the owner of the adress space may contact them, as listed in one of the five RIR databases (RIPE, ARIN etc). We always use abuse@isp.com, because this is a known adress in RIPE.
    2. The IP adress must be known as static and have a PTR-record stating it is static (mail.domain.com is acceptable).
    3. It must have a correct A-record.
    4. The TTL in of the A-record must be 86400 sec.
    If you contact them in the way they wish to be contacted (just read their website, it's not that hard), they will delist you in 24-48 hours. However, if you aren't the owner of the adress space or the simple rules are not followed, your request wil be ignored. Everyone who thinks they can't get through to sorbs just isn't reading their guidelines, it's that simple.

    --
    --- In a world without fences, who needs Gates.
    1. Re:sorbs is one the best blacklists out there by TheLink · · Score: 2

      One of the best? Really? So what's their false positive and false negative rate?

      So far in my experience RBLs have an unacceptably high false positive rate because of the way most of them work - they go by IP _ranges_.

      My email provider doesn't block spam for me, they just give it a spam ranking. I then run my email through a bayes filter, if the ISP's ranking is high enough for my comfort or the bayes thingy thinks it's spam, then it's spam.

      So far I've noticed only a few false positives (I scan very quickly through spam once in a long while - sorting by subjectline helps ;) ). And even so they weren't really false positives - they were either spamlike emails from friends/relatives (who I whitelist), or one of those chain emails.

      I once was on the verge of blacklisting one of my relatives who kept sending junk.

      Since you are an ISP, why don't you as an ISP regularly set up a bunch of decoy email accounts and start signing them up for spam? You know the usual methods. Even better if you can get few people to donate their longtime spamridden email address and they can get everyone else to no longer send emails to them. Then any email that hits multiple accounts is most likely to be junk.

      I'm sure gmail does some statistical stuff to filter out spam. I'm sure they can figure out which email accounts are "related" and which aren't. If lots of unrelated/unlinked accounts start getting very similar email that aren't from whitelists (mailing lists etc), then it's almost certainly spam.

      It's easier for an ISP or large email provider to do such things than an individual user.

      --
    2. Re:sorbs is one the best blacklists out there by Thorizdin · · Score: 2

      Sorry, but this is incorrect. SORBS does _not_ make execptions for people who follow the rules, at least not in the 8 tickets that we have had to open with them. They can be contacted via their web site ticketing system, but communication is slow, arrogant, ignorant, and inconsistent. We were able to get delisted once without paying their blackmail, but the next time we were listed they refused to even provide headers so we could locate the offender. Perhaps you were fortunant enough to only have to deal with them once, but they are far from reasonable.

  15. Re:I can't resist by sauge · · Score: 2, Insightful

    There are a large crowd of email maintainers who believe anonymous email is important for political reasons.

    I think your right on the mark though with the pharmacy analogy. We were able to implement SMTP to ESMTP quite easily so it shows people can definitely implement changes in protocols.

    I also vote with people who think black hole lists are pretty much useless these days because they swallow up so many innocent people/organizations.

    It would be nice to have an open source barracuda ( http://www.barracudanetworks.com/ns/?L=en ) like box - these things really work well.

  16. Re:SORBS!!! I'd like to ABsorb the so-and-so's!!! by Pig+Hogger · · Score: 2, Informative
    so they block me, and therefore I cannot send email to anyone using two of the major ISP's in Australia. I have emailed sorbs and asked them to check my server.
    You're shooting at the wrong duck. You're not being blocked by SORBS, but by the "two major ISPs in Australia". Your beef is with them, not SORBS.
  17. Maybe a change of tactics is in order. by kunwon1 · · Score: 3, Informative
    ORDB just shut its doors. From their closing announcement: (emphasis mine)

    We regret to inform you that ORDB.org, at the ripe age of five and a half, is shutting down. It's been a case of a long goodbye as very little work has gone into maintaining ORDB for a while.

    Our volunteer staff has been pre-occupied with other aspects of their lives. In addition, the general consensus within the team is that open relay RBLs are no longer the most effective way of preventing spam from entering your network as spammers have changed tactics in recent years, as have the anti-spam community.

    We encourage system owners to remove ORDB checks from their mailers immediately and start investigating alternative methods of spam filtering. We recommend a combination involving greylisting and content-based analysis (such as the dspam project, bmf or Spam Assassin).

    --
    Specialization is for insects. -Heinlein
  18. SpamHaus by Wdomburg · · Score: 3, Interesting

    SpamHaus is the only blacklist that I trust to do straight blocking on. We've been using them for years and have gotten a grand total of two complaints about blocked mail; in both cases the sender was on the XBL because their machine was compomised. Considering our active userbase is in the hundreds of thousands, I'd say that isn't bad at all. :)

    We actively discourage people from using SORBS. Even if they were more accurate, their removal policy is extortion.

    Any of the other blacklists out there I would recommend only as part of a scoring algorithm. Most are fairly cavalier about blocking entire netblocks even if the problem is isolated, most have no automatic aging of entries, many have poor delisting policies or are slow to respond and the false positive rates tend to vary from ok to abysmal (SpamCop, for example, doesn't seem to know the difference between a bounce message and a piece of spam... though to their credit they are fairly good about removals and provide a feedback loop so you at least know when they've tagged a message as spam).

  19. Blacklists are so 2004 by target562 · · Score: 4, Informative

    With the advent of the spam bot networks, blacklists aren't as useful for spam fighting as they used to be. Greylisting + content analysis is currently the way to go; though Spamhaus still does a decent job, but not Spamcop due to their "unsolicited bounces" thing...

  20. But pretty much EVERY ISP is spam-friendly by Anonymous+Brave+Guy · · Score: 2, Interesting

    The problem with this argument is, as usual, collateral damage. While there may be a spammer using Wanadoo somewhere, there are also many legitimate users who will be caught in the blast radius.

    Before anyone replies with the usual holier-than-thou "Well they should change their ISP then", please consider that this is not trivial for a lot of people. Moreover -- and here's the real kicker -- pretty much every ISP is "spam-friendly" because, as the recent spam wave has demonstrated all too clearly, pretty much every ISP has lots of compromised machines running on it, and those machines can be abused without the informed consent of either their owner or the ISP.

    --
    If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
  21. No one takes them seriously by Spazmania · · Score: 3, Interesting

    At this point, very few people take SORBS seriously. They're inaccurately over-aggressive. If you use it for more than your personal email, you're begging for a lot of user complaints.

    My own fun story is that they went on to my web site and subscribed their spamtraps to my opt-in email list. I didn't double-confirm, so I guess its my fault that they scammed me. SORBS then used the emails emitted from that single IP address to justify blocking 8,192 of my ISP's email addresses.

    Every other RBL maintainer has found my list to be clean. The only non-SORBS problem I've had with an RBL was with Spamcop. That was immediately resolved when the only folks who responded to further inquiry apologized for reporting the list mail by mistake.

    --
    Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
  22. Wrong Layer by jofny · · Score: 2, Insightful

    The idea of identifying/tracking/blocking content/activity/people at the IP level was always a hack at best and has long since become a complete haphazard solution. Black Lists are a bad idea that's gone on to far. Instead of putting all of that energy into building, maintaining, and implementing those lists on networks, spend some time fixing it at an app protocol or content (auth) level. Yeah, initially a lot of legit mail won't get through - but that's true of black lists as well. I know there are a lot of reasons people still do this at an IP level, but why engage in a never ending battle using methods that you -know ahead of time- will -never- solve the problem?

  23. Sorry, but you are wrong, SORBS is untrustworthy. by Dion · · Score: 2, Interesting

    Well, I have a number of servers on static IPs that SORBS think are dynamic.

    I have tried telling the idiots that they are wrong, but to no avail.

    It's really a problem that people trust such a bunch of retards, because it's hard for the administrators of the mail servers to know if important mail is being blocked, very hard for users to know and even more impossible for users to smack some sense into the the head of the fool who runs their mail server.

    What I have done in stead of using the static and poorly administered black lists is to use a number of short term, spamtrap driven blacklists, sbl-xbl.spamhaus.org which is somewhat static, but seems to be well run along with greylisting.

    With greylisting most spammers never try again and even if they do there is a good chance that they will fall into a spamtrap and be stopped by the RBL the next time around.

    I used to use SORBS (that was before I figured out they were fucking around), ORDB (which ended up taking almost no hits) and a few other lists and with the new setup I have gone from getting 70 or more spams pr. day to less than one.

    Ditch SORBS, they suck because they list much more than just dynamic addresses and refuse to fix their mistakes.

    --
    -- To dream a dream is grand, but to live it is divine. -- Leto ][