Nortel PABX hacked again

Hackers took over the Nortel-based PABX system of software vendor Legrand Software this week, ringing up to AU$1,800 of calls to Algeria in one night.

Legrand's Sydney headquarters learned of the attack on Tuesday morning, following a call by telco Optus alerting it of the huge bill rung up overnight. Earl White, sales and channel manager at Legrand, told ZDNet Australia today the hackers exploited a call forwarding feature of Nortel's BCM50 PABX.

"We believe there's a hole in call forwarding in Nortel. If you ring and get someone's voicemail, you can forward your call to someone else," he said.

Oliver Reddaway, application support engineer at Legrand, also criticised the networking equipment maker. He said he believed the Nortel codes for forwarding calls were well known in the hacking community.

"Obviously someone knows what the internal codes are to do this and the voicemail system forwards the calls. It was never made clear to us by the PABX suppliers [Nortel] that this thing could happen," he said.

Legrand's phone system, connected to a digital ISDN line, was setup around a year ago with call forwarding enabled by default. "There is stuff enabled by default that perhaps shouldn't be," said Reddaway. "There is a document out there on the Nortel Web site about this, but certainly we were never made aware of it."

The company declined to name the consultancy that actually installed its phone systems, instead blaming Nortel. "I think it's more incumbent on the suppliers of the product and service to make people aware that there are these weaknesses," Reddaway said.

Legrand has changed its phone access codes and has disabled call forwarding and international outbound calls for the time being.

The company also blamed carriers Optus and Telstra for their inability to stop the calls once discovered. "Optus don't seem to be able to tell us what's happening other than: 'You're going to get huge bills'," Reddaway said. The carrier was yet to provide Legrand with a list of the unauthorised calls.

Reddaway said once Optus informed them of the attacks, they asked the carrier to prevent repeat calls. Optus responded that it was unable to do so as the phone lines are owned by Telstra. Legrand has yet to receive any assistance from either carrier, according to Reddaway.

"It's a bit annoying that Telstra and Optus put this in the too hard basket," he said. Neither Telstra nor Optus were able to comment on the issue by press time.

Nortel said it did not wish to comment on the situation before knowing more detail. However, a spokesperson said the vendor has e-mail bulletins and Web site information devoted to preventing hacking attempts.

The attack on the Nortel PABX is similar to the one perpetrated on a NSW firm in October 2006.

Advertisement

Talkback 11 comments

    Are you Joking me? Do you work for Cisco part-time? Anonymous -- 20/04/07

    How is this hacking into a Nortel PBX? There is no breaking of code here! There are no hacking passwords!

    The installer or the company removed the default security settings. How is that Nortel's issue? If some doesn't change the administrators password on a windows box do you write an article saying Windows been hacked? No you laugh because everyone knows you need to take responsibility of security in your environment. In the telephone world that is call protecting against toll fraud. Toll Fraud requires someone from the INSIDE (and I don't mean Nortel) to open up the ports to allow call forwarding off site and you have to allow certain numbers to be dialed. In the Nortel PBX world as in all PBX vendors (Avaya, Mitel, Siemens, etc) these ports are shut off by default.

    This is a sad excuse for reporting and you need to do a little more investigation before you write false statements like this. Sounds like you got a bone to pick with Nortel, so why don't you say what’s on your mind instead of making continuous statements on a subject that you obviously have no knowledge about.

    Look in the mirror - You should only blame yourself! Anonymous -- 20/04/07

    "There is stuff enabled by default that perhaps shouldn't be," said Reddaway. "There is a document out there on the Nortel Web site about this, but certainly we were never made aware of it."

    No there isn't anything enabled by default you have to go in and turn it on and you have to allow certain dialing codes to be opened up. All of this is shut down by default. What probable happened is someone wanted to be able to have customers press 0 to dial their cell phone and reach them live. But instead of allowing just that certain number, someone allowed all numbers to be dialed.
    ------------------------------------------------------------------

    "The company declined to name the consultancy that actually installed its phone systems, instead blaming Nortel. "I think it's more incumbent on the suppliers of the product and service to make people aware that there are these weaknesses," Reddaway said."

    This is called phreaking and has been around for decades. Google it, "http://www.google.com/search?sourceid=navclient&aq=t&ie=UTF-8&rls=GGLJ,GGLJ:2006-46,GGLJ:en&q=phreaking". This is what you get for hiring a data tech to do telephones systems. Or it sounds like you had a buddy install it and you didn't want to throw them under the bus but you wanted to get your money back, so you called ZNET!

    ------------------------------------------------------------------
    "Obviously someone knows what the internal codes are to do this and the voicemail system forwards the calls. It was never made clear to us by the PABX suppliers [Nortel] that this thing could happen," he said.

    Its called pressing "0". No secret code there! What the first thing you do when you dial into a company and you don't want to hear the recording or the menu tree. Oh that’s right you press "0". This is customer whining at its best!
    ------------------------------------------------------------------

    “The company also blamed carriers Optus and Telstra for their inability to stop the calls once discovered. "Optus don't seem to be able to tell us what's happening other than: 'You're going to get huge bills'," Reddaway said. The carrier was yet to provide Legrand with a list of the unauthorised calls.”

    Since when is the job of the carriers to stop phone calls from happening? They are in the business of routing calls. How are the carrier’s supposed to know that you didn't want these calls to go through? What if you setup on purpose for your sales force to use the PBX so they don't get charged international charges on their home phone bills? Then you would be pissed that the carrier prevented your business from making money.
    ------------------------------------------------------------------

    “Nortel said it did not wish to comment on the situation before knowing more detail. However, a spokesperson said the vendor has e-mail bulletins and Web site information devoted to preventing hacking attempts.”

    Nortel didn't comment because they are not going to justify these silly comments. You should be going after your buddy who installed it or your own internal staff who opened up the ports in the first place.

    You got to be kidding me! Anonymous -- 20/04/07

    Someone better tell White and Reddaway to lock the doors of their building at night so they don't go blaming the building contractor for someone "breaking in" to their company at night.

    The reporter is an IDIOT ! Anonymous -- 20/04/07

    This reporter obviously has no idea how a phone system works.

    Maybe we should look at what happened step by step…

    1. Someone installs the PBX.
    2. The installer enables the feature to allow callers to reach them on their cell phone. Failing to enable this feature properly allowed the voicemail system to forward to any number, not just the allowed cell phone number or calls to local areas.
    3. The ‘Hacker’ keeps trying to log into mailboxes until a password is guessed correctly. Probably locking out a bunch of mailboxes in the process. (which should have been a hint) Or, they have some help from the inside getting a mailbox password.
    4. The Hacker then changes the ‘forward to’ number.
    5. The Hacker then calls in and presses the button to forward the call to a cell phone, but it is now an international number.

    So, you have a bad installer that could have prevented this, and either a really easy to guess password on your mailbox or a mole in your organization.

    Systems like this would also come with a CD of documentation, some of which no doubt mentions security issues when enabling features.

    But, the bottom line is… the PBX itself was never “hacked”. The only thing that anyone gained access to was a mailbox password. But, because of a bad installation, that one mailbox password could be seriously exploited.

    This has been done against many poorly installed systems for many years, and if the reporter knew anything at all, they would have known this. It is obvious that this reporter has an axe to grind, and that kind of reporter should NOT be working for such a reputable organization.

    Your PABX is not a fridge Anonymous -- 20/04/07

    PABX are just like PC's and Servers need correct configuration in order for them to be secure, you can't just plug them in and leave it at that.

    Voicemail systems were in the 80's that one of the most common means for "phone phreaks" to make free (to them) calls, dial into a corporate PABX, go to voicemail, login to the voicemail system with the default password (in 90% of cases there will be at least 1 mailbox with the default password or a predictable password 0000, 1111, 1234, 9999, <extension number>, etc) and then forward the line to the external number they wished to call (or in some cases dial out of another line on the PABX directly).

    Alternately as was mentioned elsewhere dial 0, then dial out, was (is?) a fairly common configuration.

    This attack has probably been carried out (assuming it wasn't just stupid configuration in the first place) in a slightly different fashion though, the likely entry was to login to a web-based configuration service which was exposed to the outside world (ergo indexable by Google, et. al., or reachable by port-scanning), most likely using the default password and then reconfiguring the switch from there.

    Nortel is not at fault Anonymous -- 20/04/07

    this issue is most likely caused by poor installation or bad administration on the part of Legrand. There is volumous documentation out there from Nortel on how to secure your system that all partners and distributors are aware of.

    The Basic function here is called Gazza -- 21/04/07

    Trunk to Trunk transfer, and it needs to be turned on to allow this kind of exploitation to take place. There may be other features on top of this or some kind of selective system such as only being able to dial out to a limited range of numbers stored in the switch, i.e. "call my mobile, or call my other number, etc, which limits what incoming callers can do.

    In my experience many customers are not prepared to lose the convenience of xfer to mobile, for instance or the added inconvenience of some extra button presses to make it happen, and demand that it be configured in the least intrusive, most automatic way, and this I think is probably what Legrand did.

    Short of this the installer has made a blunder, or are incompetent, or just did what Legrand asked them to.

    Legrand should confirm the facts and provide them before taking pot shots at Nortel, Optus or Telstra.

    Legrand need some professional consultancy for this sort of network particurlarly if they run a callcenter they clearly dont have the experience or knowledge to operate their network themsleves.

    This is not a great advertisement for Legrand or their CRM product in my opinion.

    The Basic function here is called Gazza -- 21/04/07

    Trunk to Trunk transfer, and it needs to be turned on to allow this kind of exploitation to take place. There may be other features on top of this or some kind of selective system such as only being able to dial out to a limited range of numbers stored in the switch, i.e. "call my mobile, or call my other number, etc, which limits what incoming callers can do.

    In my experience many customers are not prepared to lose the convenience of xfer to mobile, for instance or the added inconvenience of some extra button presses to make it happen, and demand that it be configured in the least intrusive, most automatic way, and this I think is probably what Legrand did.

    Short of this the installer has made a blunder, or are incompetent, or just did what Legrand asked them to.

    Legrand should confirm the facts and provide them before taking pot shots at Nortel, Optus or Telstra.

    Legrand need some professional consultancy for this sort of network particurlarly if they run a callcenter they clearly dont have the experience or knowledge to operate their network themsleves.

    This is not a great advertisement for Legrand or their CRM product in my opinion.

    Nortel Engineers point of view Anonymous -- 15/02/08

    I am a qualified Nortel engineer - and have also had this happen to a customer of ours in the UK. (their calls were diverted to Uganda, incurring a £900 bill in one weekend.)
    This is not the fault of Nortel - it is down to the customer using trivial passwords for their mailbox. Nortel mailboxes have a feature called outbound transfer, enabling you to have a message on your voicemail along the lines of "Hi i'm not here, please leave a message or press 7 to be transferred to my mobile." If the customer has a trivial password on their mailbox, and outbound transfer is enabled, then a caller reaching their mailbox can guess the password, and change the outbound transfer number to one of their choice. Then, they call back, press 7, and they are forwarded - at the phone system owners expense - to whatever number they put in.

    The solution - DONT USE TRIVIAL PASSWORDS!!!!!! Neither Nortel or the provider can be responsible for the poor security habits of users - their responsibility ends with informing users of the risks. If necessary the provider can disable this feature globally.

    Define Hacker Anonymous -- 15/02/08

    1. a person or thing that hacks.

    One who works hard at boring tasks
    - drudge, hacker

    2. Slang. a person who engages in an activity "without talent "or skill: weekend hackers on the golf course.

    3. Computer Slang. a. a computer enthusiast.

    b. a microcomputer user who attempts to gain unauthorized access to proprietary computer systems.

    That should clear upthis little preception problem my little fellows. Your all Write

    Another NORTEL PABX Dude -- 29/04/08

    I would not fully agree with the NORTEL engineer who tells that the call forwarding can be done via voicemail feature from outside
    .
    We have NORTEL PABx system installed in our company (Dubai) which got hacked last March 2008 and the Tel Bills shows numarous telephone numbers all over the world that cost extra US dollar 21017.00.

    This mean a hacker logged into the system and programmed the code in such a way that people can dial a specific number and than they are free to dial their desired no anywhere in the world.

    Anyway the Investigation is going on with the help of service provider and the Interpole police.

    My finding is that the culprit is NORTEL PABx system.

Add your opinion

Latest Videos

Sponsored content

Power Centre - Content from our premier sponsors

Blogs

  • David Braue Can not-so-smart meters help the NBN?
    It was interesting to witness Conroy's recent enthusiasm to spruik the NBN's role in supporting the Smart Grid, Smart City initiative. What a pity that Conroy hadn't yet seen the damning report from the Victorian auditor-general about that state's smart-meter roll-out.
  • Array Can the Telco Reform Act be win-win?
    In the second of our two programs looking at the Senate Inquiry into the Telecommunications Legislation Amendment Bill, we hear from shareholders, bureaucrats and industry groups.
  • Array Has New Zealand's smiling assassin delivered?
    One year into its tenure, how has the new New Zealand Government performed on issues of technology and telecommunications?
  • More blogs »

Tags

Back to top

Featured