Slashdot Mirror


Network Security Hacks

Anton Chuvakin writes "When I first got this little book called Network Security Hacks, I was unimpressed by its idea: a seemingly random collection of network security tips combined under the same cover. However, when I started reading, more and more often I exclaimed "Ah, that's how it is done!" as well as found better ways of doing what I was doing." Read on for the rest of Chuvakin's review. Network Security Hacks author Andrew Lockhart pages 312 publisher O'Reilly rating 8 reviewer Anton Chuvakin ISBN 0596006438 summary Surprisingly good; packs a lot of network security knowledge into a small book.

The book is structured around many security subjects. These are: UNIX, Windows, Network Security, Logging (covering collecting, summarizing and analyzing log files), Monitoring, (covering system and network monitoring and collecting various statistics), Tunnels (covering various kind of VPNs and encrypted communication), Intrusion Detection, and Recovery and Response (short section covering very basic forensics).

Each section has a dozen or more tips, each taking from a page to several pages. For example, looking for SUID and SGID files takes just half a page, while installing and configuring Snort NIDS takes several pages. As a result, the style is understandably terse and to-the point.

The book ended up being one cool collection of tips, ranging from mundane ('how to configure iptables on Linux') to fairly esoteric ('how to use MySQL as an authenticating backend for an FTP server'). If you've always wanted to use 'grsecurity' or 'systrace,' but thought they were too complicated - grab the book and give it a shot. If you want to set up a fancy encrypted tunnel between two networks, it covers that too. Admittedly, a lot of advice given in the book can be found on Google, but it is nice to find it in one place. Network Security Hacks covers selected topics in host security, SSH and VPNs, IDS, monitoring and even touches upon forensics. I also liked its multi-platform coverage, with a slight but unmistakable UNIX/Linux bias.

Overall, Network Security Hacks is a great book, provided you don't try to find in it something it isn't; it is a neat collection of simple network security tips. I somewhat disliked that many tips don't go beyond 'how to install a tool' and so stop short of discussing how to use it best. Another gripe: I'd rather some of the tips skipped the obvious (such as "./configure; make; make install") and focused on little known and cool ways to use technology for security. Network Security Hacks will be useful for people involved with system and network management, those starting up in the security field, as well as for more advanced professionals (as a way to check their knowledge and skills). Also, it helps folks to jump straight to effective ways of doing things in the areas where their skills are less developed.

For example, I knew it was possible to use SSH to create a makeshift VPN, but this books is the first I've seen with a really good description of doing so. Similarly, I found some neat MySQL hardening tips in the book. Overall, there is a lot in the book for most people who are somehow involved in computer security, particularly if they're also running UNIX or Linux.

Anton Chuvakin, Ph.D., GCIA, GCIH is a Senior Security Analyst with a major security information management company, author of Security Warrior (and contributor to Know Your Enemy II), and maintainer of security portal info-secure.org You can purchase Network Security Hacks from bn.com. Slashdot welcomes readers' book reviews. To see your own review here, carefully read the book review guidelines, then visit the submission page.

107 comments

  1. Happy Day! by Anonymous Coward · · Score: 5, Funny

    I've been beating myself over the head trying to find a gift for my Script Kiddie nephew! Thank you Andrew Lockhart!

    1. Re:Happy Day! by brxndxn · · Score: 2, Funny

      Looks like your funny comment was moderated by a script kiddie who took it seriously...

      --
      --- We need more Ron Paul!
  2. Hmmm by Neil+Blender · · Score: 5, Funny

    "Network security hacks" - sounds like some setups I know of.

    1. Re:Hmmm by Anonymous Coward · · Score: 1, Funny

      Hey, man -- are you making fun of my network?

    2. Re:Hmmm by Anonymous Coward · · Score: 0

      Call Microsoft tech support. They'll tell you how to get around product activation and a lot of other annoying security features. Be sure to give them your full name and home address when you call.

    3. Re:Hmmm by stor · · Score: 2, Funny

      "Network security hacks" - sounds like some setups I know of.

      Heh, sounds like some techs I know.

      Cheers
      Stor

      --
      "Yeah well there's a lot of stuff that should be, but isn't"
  3. Good book by xOleanderx · · Score: 5, Interesting

    Its a very good reference book. If anyones looking for a good beginners book thats similar tho this one then check out Steal This Computer Book 3: What They Won't Tell You About the Internet

    1. Re:Good book by nacturation · · Score: 4, Funny

      If anyones looking for a good beginners book thats similar tho this one then check out Steal This Computer Book 3: What They Won't Tell You About the Internet

      A note to other geeks out there: I had to learn the hard way that, yes officer, you are expected to purchase this book before leaving the store.

      --
      Want to improve your Karma? Instead of "Post Anonymously", try the "Post Humously" option.
  4. Beginner's book by Zorilla · · Score: 4, Interesting

    From what I read in the review, it looks more like a beginner's guide to network security. It could prove to be quite useful for someone fairly new to it. In the Air Force, quite a few people who deal with IT are pretty new to this stuff (a lot of people are straight out of high school), and even though most stuff we deal with is Windows-centric, we still need to know Unix for things such as firewalls. Looks like the book could be handy for both.

    --

    It would be cool if it didn't suck.
    1. Re:Beginner's book by 0racle · · Score: 4, Interesting

      In the Air Force, quite a few people who deal with IT are pretty new to this stuff.
      Anyone else more then a little bothered by this statement?

      --
      "I use a Mac because I'm just better than you are."
    2. Re:Beginner's book by itwerx · · Score: 1

      In the Air Force, quite a few people who deal with IT are pretty new to this stuff.

      Anyone else more then a little bothered by this statement?


      Bothered/insulted or bothered/worried?

    3. Re:Beginner's book by 0racle · · Score: 2

      Well Military sites have got to be high on the list of sites for random break in attempts, and while I would hope sensitive materials would be under very good lock and key, sometimes they make you wonder. Personally, I would have thought that the people covering their security would be more then a little familiar with what they were doing.

      Though it a nice little insult to everyone trying, they don't care so much that someone who has never done security before can handle all those pansy ass hackers.

      --
      "I use a Mac because I'm just better than you are."
    4. Re:Beginner's book by lylonius · · Score: 4, Interesting

      I have an O'Reilly Safari account and checked out several recent "security" titles:
      - Network Security Hacks
      - Network Security Assessment
      - Security Warrior

      and I have to say that all of them have weak content.

      I don't proclaim to be an expert by any means, but security cannot be administered in such small nuggets of mostly outdated tricks/hacks.

      Example: Hack 40: Block OS Fingerprinting. It briefly mentions nmap's -O option and then immediately demonstrates a fairly complex pf filter on OpenBSD. Does the author explain _any_ of the valid and invalid TCP flags that nmap uses? no. Does the author explain any adverse affects of silently dropping _all_ traffic that is satisfied by this complex ruleset? no. Does the author ever mention passive OS fingerprinting? Does it even mention the simplest/non-intrusive methods used to fool active OS fingerprinters like changing the IP default TTL or manipulating the TCP initial sequence number generation parameters? How do we port these rulesets to ipfw? netfilter? PIX conduits? In short, for this rule to be the slightest bit useful, we must assume that it works perfectly (does not drop a single legitimate frame/packet/segment) and simply cut-and-paste this solution in to our bastion host and hope it works.

      In that sense, you might as well be dealing with the Windows-centric mindset of cut-and-paste and hope it works.

    5. Re:Beginner's book by Anonymous Coward · · Score: 0

      Ever heard of Military Intelligence? Niether have I.

    6. Re:Beginner's book by Anonymous Coward · · Score: 0

      The fact that the submitter claims this is the first good guide to making a VPN with SSH would indicate they have not been around very long and haven't yet discovered the Linux HOWTO guides.

      SSH/PPP VPNs are the oldest documented method of creating a VPN on linux. Have a look at www.tldp.org, check the VPN guide.

      VPNs with SSH/PPP, and it was released in 1999.

      linky

    7. Re:Beginner's book by lylonius · · Score: 1

      The fact that the submitter is one of two co-authors of Security Warrior speaks volumes about the quality of that book as well.

    8. Re:Beginner's book by Anonymous Coward · · Score: 0

      How many organizations out there can boast a completely competent IT staff? Funny, I haven't seen many. I see an awful lot of organizations whose IT staff are made up of varying degrees of competencies, and experience. As for the US military, keep in mind that many of the IT staff consists of very young people fresh out of High School. Is this really scary? No, because, just like most IT staff I've seen, you'll have competent (or semi-competent) people teaching the younger less experienced staff.

  5. Google by Roland+Piquepaille · · Score: 5, Insightful

    Admittedly, a lot of advice given in the book can be found on Google, but it is nice to find it in one place.

    Well duh...

    Google knows everything, therefore includes any book, just like sea water contains sugar (and almost any known chemical compound) but it's so diluted it would make a lousy sweetener. Therefore, books are good, whether or not Google contains the information in the book.

    1. Re:Google by ovit · · Score: 0

      Google knows everything huh? How about all of the Potential pages built dynamically as the rusult of DB queries? Do google know about all of that information? It seems to me that this is the really interesting stuff, and all google would know about would be the page where you enter you're query...

      Tony

    2. Re:Google by Neil+Blender · · Score: 5, Insightful

      Google knows everything huh? How about all of the Potential pages built dynamically as the rusult of DB queries?

      Google groups knows damn near everything. I have been using it since it was Deja News and I have to say, I have learned more from it than the next top ten resources at my disposal combined. Type in the most specific keywords and 'Re' (this gives you reponses to questions) and you will get answers fast. Google groups is god.

    3. Re:Google by Anonymous Coward · · Score: 2, Funny

      Google knows everything, therefore includes any book, just like sea water contains sugar (and almost any known chemical compound) but it's so diluted it would make a lousy sweetener. Therefore, books are good, whether or not Google contains the information in the book.

      Can you write this u into a "technology trends" article and submit it to slashdot?

    4. Re:Google by BigDave81 · · Score: 5, Funny

      Yes, but does google know what i'm thinking right now??

    5. Re:Google by Anonymous Coward · · Score: 5, Funny

      Yes, but does google know what i'm thinking right now??

      yes

    6. Re:Google by Anonymous Coward · · Score: 0
      Why yes, Google can direct you to a large selection of "large women" pages.

    7. Re:Google by Nasarius · · Score: 5, Funny
      Google groups is god.

      Agreed. It's a wonderful supplement to MSDN when Microsoft neglects to tell you how to actually use their own APIs.

      --
      LOAD "SIG",8,1
    8. Re:Google by Ryosen · · Score: 2, Insightful

      No doubt he put that comment there to head off the obvious, non-essential and (frankly) lame comments from others who post "big deal, I can find this info on google." Which is fine. But I can find it all in this $16 book much quicker...and it's indexed.

      --

      Ryosen
      One man's "Troll, +1" is another man's "Insightful, +1".
    9. Re:Google by thelibrarian · · Score: 1

      That would be all the time wouldn't it?

      In my experience, C# is not too bad a language, and has some nice improvements over Java 1.4, but the documentation is nowhere near as good.

    10. Re:Google by burns210 · · Score: 1

      "Google knows everything, therefore includes any book, just like sea water contains sugar (and almost any known chemical compound) but it's so diluted it would make a lousy sweetener."

      Wow... this 'Goo-gel' sounds pretty interesting. if you ask me, these guys should make some sort of filtering software based on keywords found in all that 'diluted' seawater, so as to be able to retrieve only relavant information for a person... maybe if they used some web-based application, or interface.... but they would have to kepp it simple! Not too many pictures or links or crap on the frontpage, just an area to type and a button, or something...

      aw, what do I know, anyway?

    11. Re:Google by sapgau · · Score: 3, Insightful

      Its a catch 22. Google knows everything as long as you ask with the right keywords (i.e jdbc, rmi, DCOM, etc.) If you have no idea what acronyms to include in your query then you are stuck. A good place to get a starting point on the acronyms is reading them from a book!!! :o)

    12. Re:Google by Anonymous Coward · · Score: 0

      That's uncanny, that is.

    13. Re:Google by Anonymous Coward · · Score: 0

      isn't google indexed? ;o)

    14. Re:Google by WuphonsReach · · Score: 2, Insightful

      Its a catch 22. Google knows everything as long as you ask with the right keywords (i.e jdbc, rmi, DCOM, etc.) If you have no idea what acronyms to include in your query then you are stuck. A good place to get a starting point on the acronyms is reading them from a book!!!

      Or subscribe to a good technical rag, or skim the newsgroups or mail lists regularly.

      As they like to say, "Knowing is half the battle"... yeah, simply knowing that something exists and what it might be called. I may not know anything about SYN floods today, other then they exist and are generally used as an attack mechanism. But that's plenty enough information to enable me to go read up on them in a few hours for when I really need that knowledge.

      I can't know everything, but I make sure I know where to find out.

      --
      Wolde you bothe eate your cake, and have your cake?
    15. Re:Google by boinger · · Score: 1

      I love it when "They" is GI Joe.

      --
      Send your friends messages of love at fuck-you.org
    16. Re:Google by Anonymous Coward · · Score: 0
      ovit (246181) writes:
      How about all of the Potential pages built dynamically as the rusult of DB queries?
      And now Google knows you can't spell result.
  6. "Ah, that's how it is done!" by blue_adept · · Score: 5, Funny

    why can't I shake the image of Wyle. E. Coyote reading his Acme book of Hacking just before trying something he's about to reget...

    --

    "Is this just useless, or is it expensive as well?"
    1. Re:"Ah, that's how it is done!" by Anonymous Coward · · Score: 0
      why can't I shake the image of Wyle. E. Coyote reading his Acme book of Hacking just before trying something he's about to reget...
      You fiend! Now I'll have that in my head for days....

      At least.

  7. You could just google the table of contents by Fiz+Ocelot · · Score: 3, Interesting

    You could probably just look at the table of contents of this book and do a search on each section/topic. Actually I might try just that, might turn up some interesting stuff.

  8. sorry ...but im not impressed by brunokummel · · Score: 3, Insightful

    with a title like Network Security Hacks I would expect much more than teaching me how to install a program on my computer or how to use SSH to tunnel a connection like the reviewer has said.
    Sorry if im being mean but you can learn just as much by reading the manpages or by using google after the how-tos.
    If you really want to learn something useful about networks I suggest the good old Richard Stevens

    --
    What is best in life? To crush your enemies, to see them driven before you and to hear the lamentations of their women.
    1. Re:sorry ...but im not impressed by Anonymous Coward · · Score: 1, Informative

      Nice but couldn't you post the ed2k link?

      God damn, fine, I'll do it myself.

      Addison Wesley - TCP-IP Illustrated Volume 1 - The Protocols (W. Richard Stevens)(1993).chm

      Damn lazy kids.

  9. Author's /. ID by Anonymous Coward · · Score: 0, Troll
  10. Re:Too dumb for college? by Anonymous Coward · · Score: 0, Funny

    yvan eht nioj

  11. duh by Anonymous Coward · · Score: 0

    Ah, that's how it is done!"

    In other words, a public admission you've ignored proper procedures in the past and fessed up to knowing just enough to be dangerous.

  12. O'Reilly discount by MrWa · · Score: 4, Informative
    There is currently a $20 mail in rebate for this book at Fry's (and elsewhere?). On the 4th, this book and "Windows XP Hacks" were reduced to $20, so you only had to pay sales tax.

    This deal ends today (7/8) so hurry out:
    Hackers and Painters
    Network Security Hacks
    Windows XP Hacks
    Hardware Hacking
    Ipod and Itunes: The missing manual
    Hardware Hacking projects for geeks
    Adobe photoshop CS one on one
    Mac OS X Panther: the missing manual

    1. Re:O'Reilly discount by john_smith_45678 · · Score: 1

      Hackers and Painters

      What...?

  13. Call me weird... by bladesjester · · Score: 2, Informative

    Personally, the TCP/IP author i perfer is Comer, but then that's what i cut my teeth on. Also doesn't hurt that Comer was the advisor of my favorite CS prof in my undergrad career. (because he not only knew what he was talking about, but he could also teach and made things interesting. Not an easy person to have classes with but fair and fascinating)

    --
    Everything I need to know I learned by killing smart people and eating their brains.
  14. best, cheapest way to test network security by spacerodent · · Score: 4, Funny

    The fastest, best, AND cheapest way to test network security is to load up an irc client on it and go to a linux channel. Then simply talk about how your "windows" system is unhackble.

  15. First tip: Secure mountpoints by mcgroarty · · Score: 4, Informative
    The first tip covered is securing mountpoints. Did you know you can mount some volums so that suid bits don't work on them, or so you can't even execute files on them?

    This is a biggie. You can prevent users from creating code in /home if you want, and you can keep runnable stuff out of /tmp or /var.

    Debian does a really great job of keeping those paths pure so that packages don't rely on them having runnable things. This means great strides in security if you mount with those options, save one terrible exception: dselect wants to run scripts in tmp :(

    1. Re:First tip: Secure mountpoints by Anonymous Coward · · Score: 3, Informative

      Yes, in fact openbsd mounts various partitions noexec, nosuid, etc by default.

    2. Re:First tip: Secure mountpoints by PacoTaco · · Score: 5, Informative
      You can prevent users from creating code in /home if you want

      Not quite. You can still run stuff as an argument, like:

      perl /home/pacotaco/something.pl

    3. Re:First tip: Secure mountpoints by Q2Serpent · · Score: 1

      Except:

      a) you aren't executing the script, you are executing perl

      b) it's aweful hard to exploit anything that way, where as if you place an executable called 'ls' in /tmp and someone has '.' in their path, and happens to be in /tmp, they will run your script without knowing it

    4. Re:First tip: Secure mountpoints by Anonymous Coward · · Score: 1, Informative

      The worst interpreter for this is in fact the userland ELF linker, ld.so. For example:

      # chmod -x /usr/bin/xmms
      # /usr/bin/xmms -v
      bash: /usr/bin/xmms: Permission denied
      # /lib/ld-linux.so.2 /usr/bin/xmms -v
      xmms 1.2.10
    5. Re:First tip: Secure mountpoints by Anonymous Coward · · Score: 1, Interesting

      Wow this I didnt know, I always thought this was the worsed:

      #!/usr/local/bin/tcc -run
      #include
      int main(int argc, char **argv)
      { /* place your C Code here */
      return EXIT_SUCCESS;
      }

      But the Tiny C Compiler arent in the default installs.. and this doesnt even come close to yours

    6. Re:First tip: Secure mountpoints by Anonymous Coward · · Score: 0

      You're executing the script inside the perl virtual machine emulator. Please go back to Computing 101 where we talk about Church-Turing and the concept of the universal computer.

    7. Re:First tip: Secure mountpoints by Anonymous Coward · · Score: 0

      ld-linux and gdb spring to mind

  16. Goverment has its nose in everything by SolidCore · · Score: 0, Offtopic

    Representatives of government and industry already have begun addressing the needs of specific infrastructure sectors, but the partnership is intended to bring together these efforts to facilitate a broader industry dialogue and to serve as a catalyst for action, according to the release. Government and industry representatives will meet again early next year to identify and begin addressing specific areas of mutual interest.

    1. Re:Goverment has its nose in everything by Anonymous Coward · · Score: 0

      Umm, does that mean if I buy this book using a credit card my name will go in a government database, filed under "possible hacker threat"?

  17. Why is military IT not as good as it could be? by attemptedgoalie · · Score: 4, Insightful

    Wonder why the Air Force and other military branches don't have superior IT staff?

    When their time to re-enlist comes up, they can take that knowledge (and security clearance) and go get paid 5-10 times what the service pays them to work for a contactor to the NSA, FBI, CIA, or the big defense contractors.

    Why would you stay?

    Wonder why there are so many guys not re-enlisting? Is it that they don't want to serve or go back to Iraq? Nope. They see the private security guys there making 10-20 times what they make for the same job...

    I see a trend here.

    --
    My mom says I'm cool.
    1. Re:Why is military IT not as good as it could be? by itwerx · · Score: 1

      Good point. I got out early, (intentionally RIF'd smartass :), and even without the security bit just some basic networking knowledge got me twice the pay immediately.

    2. Re:Why is military IT not as good as it could be? by OhHellWithIt · · Score: 2, Insightful

      The financial incentive was there before 9/11. Several years ago, a college friend who has a B.S. in mechanical engineering let slip the amount of her naval officer's pay. It was about 2/3 what I was getting in private industry with a liberal arts degree. Knowing her personality, she wasn't in it for the money, but out of dedication to the U.S.

      It really bugs me that our military personnel get the short end of the stick, financially, when they face risks most of us do not. (After all, did YOUR boss decide to invade Iraq?) I've heard that U.S. soldiers returning from Iraq on leave are responsible for paying their own transportation from wherever the military drops them when they hit the ground. IMHO, they deserve a first class ticket from there back to their families.

      --
      "Who controls the past controls the future. Who controls the present controls the past." -- George Orwell
    3. Re:Why is military IT not as good as it could be? by wronskyMan · · Score: 1

      True, the military pay is lower in absolute terms (especially early on), but consider the following scenarios:

      Geek 1:
      1. Go to college for CS for 4 years
      2. Graduate with 30K student loan debt
      3. Spend months looking for job
      4. Working at Walmart at 62 to work off the effects of said student loans, several medical bills incurred during breaks between jobs with no health insurance, and no retirement savings
      5. ???
      6. Profit

      Geek 2:
      1. Enlist at 17 (or commission after college at 21-22)
      2. Military medical care for you+dependents during active duty
      3. Military paid education (college for enlisted, grad school/ROTC/both for officers)
      4. Retire after 20 years at 37 for enlisted, 41-2 for officer
      5. Retiree TRICARE health benefits
      6. Several K/month retirement pay with cost of living increases for *life* (50% of average salary for last 3 years in military) (avg ~2k for enlisted, more for officers)
      7. Start new high paid civilian career
      8. ???
      9. Retire again/Profit

      Geek 2

      --
      --- You shall know the truth, and the truth shall make you mad- Neal (not Cowboy) Boortz
  18. Haven't finished it yet... by atomic-penguin · · Score: 4, Interesting

    I was lucky enough to get a review copy from O'reilly. One of the first things I tried was faking your OS signature for port scans. It was interesting to try it out, but I had to downgrade my Linux Kernel to 2.4.18 *gasp*. So after a recompile, and configuring iptables for IP Personalities, nmap detected "Sega DreamCast Console" on aforementioned machine. There are other signatures, I just wanted to try out the most amusing one. The problem is the patch is deprecated, buggy, not being developed, and the sparse documentation mentions it can make your TCP sequences less secure. Hey, it was amusing to try it, but too much hassle, and maybe it is not the most secure solution. Don't know what this one was doing in a security book, considering it could cause your system to be less secure. Nmap detects the faked signature about 90% of the time, depends on how the network is routed and such.

    Most of the Windows hacks are a matter of downloading 3rd party software, however there was one registry hack to turn off Default SMB shares (C$ and ADMIN$), this was the only Win Hack.

    I have enjoyed reading so far, and will get around to finishing it...eventually. Much like the other hack books there are hacks in here for beginners, intermediates, and wizards.

    --
    /^([Ss]ame [Bb]at (time, |channel.)){2}$/
    1. Re:Haven't finished it yet... by shish · · Score: 1

      I got OS confusion to work with no kernel hacks - I have a windows (98) box as my gateway, with ports forwarded to all my linux (2.6) boxen behind it - the mix of windows replies and forwarded linux replies results thusly:

      Starting nmap 3.50 ( http://www.insecure.org/nmap/ ) at 2004-07-09 11:17 GMT
      Interesting ports on cafe (192.168.0.1):
      (The 1647 ports scanned but not shown below are in state: closed)
      PORT STATE SERVICE
      20/tcp open ftp-data
      21/tcp open ftp
      80/tcp open http
      113/tcp open auth
      240/tcp open unknown
      640/tcp open unknown
      666/tcp open doom
      1337/tcp open waste
      Device type: media device|general purpose
      Running: Turtle Beach embedded, Microsoft Windows 95/98/ME|NT/2K/XP
      OS details: Turtle Beach AudioTron 100 network MP3 player, Microsoft Windows NT 3.51 SP5, NT 4.0 or 95/98/98SE

      --
      I mod down anyone who says "I will be modded down for this", regardless of the rest of their comment
    2. Re:Haven't finished it yet... by Anonymous Coward · · Score: 0

      Next thing, this guy's gonna talk about how his 98 system protects his Checkpoint firewall from those nasty hackers.....

  19. BOFH hack -- restricted shell by atomic-penguin · · Score: 5, Interesting

    bash-2.05b$ bash -r

    bash: SHELL: readonly variable

    bash: PATH: readonly variable

    bash-2.05b$ ls

    bash: ls: No such file or directory

    bash-2.05b$

    Now users cannot run anything that is not symlinked to their home directory.

    --
    /^([Ss]ame [Bb]at (time, |channel.)){2}$/
    1. Re:BOFH hack -- restricted shell by fuzzybunny · · Score: 1

      Why restricted? All you need to do is hack MudSH to be a bit more, uh, challenging to your users ("You turn left into /etc. A giant firebreathing dragon labelled 'root' awaits you.")

      --
      Cole's Law: Thinly sliced cabbage
    2. Re:BOFH hack -- restricted shell by Anonymous Coward · · Score: 1, Informative

      Restricted shell is more of a security illusion than anything else. From apps ran from it, no restrictions occur. i.e. if vi/vim is linked, then a simple :!cmd executes any cmd. As you can't rely on the "authorized" app security level, there are no inforcement with restricted shells, therefore no use.

      My 2 cents...

    3. Re:BOFH hack -- restricted shell by Markzilla · · Score: 0

      I can keep my dog in the yard by cutting off his legs and blinding him.. But what good is a blind dog with no legs?

    4. Re:BOFH hack -- restricted shell by Col.+Panic · · Score: 2, Funny

      you've never supported end users, have you?

  20. U Stupid by Anonymous Coward · · Score: 0

    Restricted shells are primarily useful for cases where you're trying to avoid shooting yourself in the foot, not where you need to stop a
    possibly malicious user.

    1. Re:U Stupid by Anonymous Coward · · Score: 0

      In its defense the book does mention that you may only want to use it if you trust your ussers to some degree, but don't want to go through the trouble of setting up a jail for them to use and don't want them exploring the system

  21. snort setup by AmishSlayer · · Score: 5, Interesting

    I've just finished a setup with snort, apf, logsurfer and a custom program to create a live repsone firewall.

    snort will detect the offensive network traffic and put it into the alert log file. Logsurfer will then trigger and email me with a notice, it will run a program I wrote to blacklist the attacking IP (my program checks to make sure the IP is not already banned and makes sure the IP is not my own so I do not get locked out). Finally, my program updates the firewall to block the bastard.

    The only hole I see in this setup is a DoS by attacking with different spoofed "from IPs" until the firewall rules are too big, or too many legit servers are banned.

    1. Re:snort setup by ganast · · Score: 1

      Cool, do you have this blogged somewhere? I am interested in reading more if you have written anything on the setup.

      --gabe

    2. Re:snort setup by Anonymous Coward · · Score: 0

      or snort itself having a hole.................

    3. Re:snort setup by kiowa · · Score: 1

      Put in a timeout for your rules and you'll be safer as well in case of a DoS directed at your dynamic firewall. For example if you let every dynamic rule have a lifetime of 10 minutes before it gets deleted again it'll cut down on how many rules there are in your iptables setup, and limit the risk of being shut off from someone for a longer time-period.

      --
      =-kiOwA-> EOF
    4. Re:snort setup by Anonymous Coward · · Score: 1, Informative

      This has been done to death when portsentry was released shortly followed by fuckportsentry.pl that could cripple any machine running it.

      The exploit uses the method you describe, spoofing the source addresses so you block a machine that you should actually trust.

      If you use snort then you've upped the stakes a bit in that the spoofed traffic is quite a lot harder to create but its not impossible. You only need to lose DNS access and the system will be knackered.

      It's a nice idea, pro-active IDS, but unfortunately until the world implements proper egress filtering then it will probably be exploitable. You can reduce the odds of being caught by doing things like rate-limiting the addition of new firewall rules, I've yet to see one of these systems that I couldn't mess up though, and I'm hardly a master hacker.

    5. Re:snort setup by joshmccormack · · Score: 1

      Are you familiar with snort2pf?
      What do you think of it? How does it compare with what you've done?

      And how about the Snort DDOS rules?

    6. Re:snort setup by AmishSlayer · · Score: 1

      If you use snort then you've upped the stakes a bit in that the spoofed traffic is quite a lot harder to create but its not impossible. You only need to lose DNS access and the system will be knackered.

      Fortunately, I have whitelisted important services like DNS. But I am still very cautious about this, because it is actually much easier than you might think to trigger a positive (or even a false positive) for snort. A false positive for example would be, IIRC, sending an email (accepted or not) that does not have a newline character within 100 characters of the Content-Type header. This would be trivial to manufacture and is part of the default set of snort rules. I am sure there are other ones out there with smaller payloads for a more efficient attack. Thanks for the input, it has been very helpful :)

      Are you familiar with snort2pf [gnu.org]?
      What do you think of it? How does it compare with what you've done?


      Actually, no. I tried to find tools that did this for me, but instead I ended up making my own. Reading the description for snort2pf, it appears as though it just checks the alert for dangerous entries... it looks like a nice all in one package.

      What my setup is able to do is to handle different log files and I can handle nuisance traffic too. Like http_access referrer spam (you know those damn entries for surfcorp.com/s.php?uid=1234&key=value&key= etc ) I get hundreds of bad requests from Austrailia computers so I use this to ban the IPs....

      Cool, do you have this blogged somewhere? I am interested in reading more if you have written anything on the setup.

      sorry no blog, but this has motivated me to get one going. However, my setup does need some work before it would be worth making public.

  22. Book scripts download. by prabha · · Score: 1

    Can someone point me to a download link for the scripts used in that book.
    Thanks in advance.

  23. cool, looks good by Nexcet · · Score: 1

    i'll check it out though, thanx :)

  24. SecurityFocus.com by truG33k · · Score: 1

    While a good book is always great, most of this stuff is already on SecurityFocus. Not to mention is home of the bugtraq mailing list. I find alot of the material is already covered in their infocus articles, plus some of the best hackers out there, both white hat and black hat, are on the list and give some of the best tips.

    --
    You only live once, so you might as well have fun before you die.
  25. sure by Anonymous Coward · · Score: 0

    > Admittedly, a lot of advice given in the book can be found on Google, but it is nice to find it in one place.

    Translation: too lazy to find it myself, I'll just eat some potato chips and pay the man for his "research."

  26. Faking Signatures by The+Angry+Mick · · Score: 1

    While its often funny as hell to set a server signature to something like "General Electric Toaster Oven, Microsoft Windows 3.11", I gotta wonder if doing this results in more malicious pokes at a system? Obviously a hardcore cracker is gonn know its bogus, and I'm willing to bet this only makes him/her more determined to correctly identify the target.

    Anybody have some stories/thoughts/example data?

    --

    I'm not tense. I'm just terribly, terribly, alert.

  27. gilderoy? by Anonymous Coward · · Score: 0

    are you sure it isn't gilderoy lockhart? the same author of 'magical me'?

    or did he change his name after coming out of st.mungo's?

  28. O'Reilly's weak security titles by jombee · · Score: 1

    I am a security professional and also have an O'Reilly Safari account. I agree completely with you, lylonius. O'Reilly has few good security titles at all. The SSH, OpenSSL, and Kerberos books are the only ones I have kept on my Safari bookshelf for long.

    Looking at my bookshelf in the office, the publishers of security titles I actually purchase from so as to have the hardcopy available for reading/reference/travel are New Riders, Syngress, and Auerbach. O'Reilly isn't represented.

    = jombee

    1. Re:O'Reilly's weak security titles by lylonius · · Score: 1

      There was a thread (RE: TCP/IP skills) today on the security-focus pen-test mailing lists discussing something similar and I think the book Network Security Hacks is a perfect example. Each trick/hack demonstrates a high-level concept applicable to a single tool.

      So, the argument is, is it sufficient to be well-versed in tools or is it more important to possess a strong understanding of the underlying protocols?

      Of course, we could take it to another level and ask why there are so many books that take a bottom-up approach, as opposed to looking a security as a process and beginning the discussion of security using high-level goals. I'd be interested in a comprehensive book that looks at security by assessing risk, modelling threats, defining a TCB, and finally using the tools/technology that satisfy those requirements.

    2. Re:O'Reilly's weak security titles by AuMatar · · Score: 1

      ITs always more important to know the underlying principles than a tool. Tools change, principles don't. And principles will help when something not covered by the tools occurs.

      AS for why books don't act like that- two reasons. First, many people want the lowdown on the tools so they can put it on their resume. Second, its easier. A lot easier. A lot of people writing these books don't understand the concepts, and even fewer who do can explain them. Forget the old saw about those who can't teach- teaching takes skill, especially teaching abstracts. Notice how there's also 100s of books on C++ and Java syntax, but few to none on how to design even simple programs?

      --
      I still have more fans than freaks. WTF is wrong with you people?
  29. Google is often a two step process by Dog135 · · Score: 1

    What I usually do is a generic search (ie: network security phrases) to find the keywords to use on a proper search. Works great, even if it is a two step process.

    For instance, I heard about a liquid that will solidify in the presence of a magnetic field. I type "liquid solidify magnetic field" into google. Then, looking though the pages, I find the term "magnetorheological fluid", which makes a much more refined search.

    --
    "That's so plausible, I can't believe it!" - Leela
  30. Wyle E. Hacker by Dog135 · · Score: 1

    I can just see it:

    Wyle E, sitting in front of a computer trying to hack the nation's defense computers to use starwars satellites to send a deathray down to the road runner's location.

    Thought bubble appears showing the roadrunner turning into a cooked turkey.

    After a short time, the screen flashes red. Wyle E. starts wiping his HD and eating his printouts and disks.

    Just as he finishes, the FBI break in and arrest him. Next, we see them holding Wyle E. over a plastic bag, waiting for the evidence to drop out.

    --
    "That's so plausible, I can't believe it!" - Leela
  31. Re:Does it know about, Garfield's OUT IN THE STREE by Anonymous Coward · · Score: 0


    No, google does not know this.

    Does Google know about Garfield's OUT IN THE STREETS ? I don't think so. An LP from 1977, with the marvelous "A Private Affair" tune.

  32. Do they know about Garfield's OUT IN THE STREETS ? by Anonymous Coward · · Score: 0



    No, google does not know this.

    Does Google know about Garfield's OUT IN THE STREETS ? I don't think so. An LP from 1977, with the marvelous "A Private Affair" tune.