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Malicious Faxes Leave Firms 'Open' To Cyber-Attack (bbc.com)
Booby-trapped image data sent by fax can let malicious hackers sneak into corporate networks, security researchers have found. From a report: Since many companies use fax machines that are also printers and photocopiers, they often have a connection to the internal network. The malicious images exploit protocols established in the 1980s that define the format of fax messages. The research was presented at the Def Con hacker conference in Las Vegas. The two researchers said millions of companies could be at risk because they currently did little to secure fax lines. "Fax has no security measures built in -- absolutely nothing," security researcher Yaniv Balmas, from Check Point software, told the BBC. Mr Balmas uncovered the security holes in the fax protocols with the help of colleague Eyal Itkin and said they were "surprised" by the extent to which fax was still used.
How exactly does this work, is this some sort of injection attack- where a badly formatted image file somehow includes code to take over the fax machine's operating system instead?
If so this is really poorly designed- an incoming fax should be isolated from everything except printing off the incoming fax.
"That's the way to do it" - Punch
Maybe we can finally get rid of one of the klugiest pieces of technology ever invented. Email anybody?
Faxes are still used, whether digitized or old-fashioned, because of the court system. A signed and faxed form carries the weight of a physical contract. A signed and emailed form does not.
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Fax machines aren't replaced by emailing scans. They are being replaced by holding documents up in front of a smart phone camera.
Scanning and emailing a document - where it can be FWD: FWD: FWD: ... - is unacceptable.
And in many jurisdictions, it's not considered legally valid if you email it.
Besides, emails (unless encrypted, yea everyone does this), are simply postcards in the mail.
Anyone can read them with a little effort.
I would not want my SSN scanned and then sent via email, vs faxed.
Seems some can't let go of their stereotypes.
T.38
https://en.wikipedia.org/wiki/T.38
T.37
https://en.wikipedia.org/wiki/T.37
I can't believe that nobody's noted that Elliot in Mr. Robot used a faked Fax to get access to Police data: https://www.theverge.com/2016/...
Mimetics Inc. Twitter
If the comment "We can only accept a fax of the original document" still is being said fax will always be around. Who says I didn't make it PDF and print the PDF 100 times and fax you the last copy? People have asked to fax checks. There is no end to the misunderstanding of faxing.
I've been retired for a couple of years, but we always had to keep a POTS line around for the fax ( burglar alarm too ) as fax wasn't reliable over VOIP. If faxing over VOIP can't be / hasn't been fixed then the migration to VOIP should kill off fax sooner than later.
You live and learn, or you don't learn much.
Which is why I'm so disappointed smartphones cannot send an actual fax from that photo, while there is no technical reason they could not. You'd create interop that way. But of course nobody is interested in that sort of thing, when we could pretend for progress by throwing out useful working stuff instead.
Just like I'm disappointed --again-- by the idiots making a big fat ruckus about a piece of otherwise useful technology as if it's all broken, when in fact it's a small corner case in a limited range of a certain manufacturer's products. Of course that needs fixing, but "reporting" like this makes it seem all faxes are a giant backdoor in every organisation, which simply isn't true.
Thanks for breaking it, "hacker" idiot wannabe-heroes.
I imagine that if you could reverse engineer an uncommon operating system running on an embedded computer with just serial output for debugging, dig through binary application code and find an exploitable bug in a custom JPEG decoder, you would not be overly offended by some loudmouth anonymous coward calling you an idiot wannabe-hero. I'd expect it is somewhat like people calling me a cheater when I obliterated them in online FPS. Always a good chuckle.
That's because fax is simple. It's a technology that's really boiled down what it does to the ultimate in simplicity.
To set it up, you connect it to a phone line and power. You can set it up further if you want, but as far as its basic needs, they've been met.
To send a fax, you stick the paper into the document reader, dial the number and press start. The machine will figure out what to do and your pages are magically sent off to the recipient. Hope you got your number right.
To receive a fax, you really do... nothing. It just sits there and answers the phone.
Some fax machines even print you a receipt after it's done.
Brain dead simple.
Try emailing a scan to someone, and how many steps that requires - from scanning the document to your computer and then attaching it to send out. Even with software that automates it all, it's still not quite dump it, push it, and forget about it.
If you have a fancy scanner, it may allow you to scan to email so you can almost do it by entering the recipient's email at the machine. But few scanners do this.
You're far more likely to just have someone take a photo of the document and send it via mms or something.
To send a fax, you stick the paper into the document reader, dial the number and press start. The machine will figure out what to do and your pages are magically sent off to the recipient. Hope you got your number right.
A previous company I worked for had the fax number incorrect on a lot of their documentation that was handed out to clients, including fliers and business cards. The number listed as a fax number for the company was actually an "adult services" phone number. We never found out if that was done intentionally as a joke by someone or just a simple error. (the number was two digits off the correct fax number).
No client ever reported a problem and to my knowledge the mistake was never discovered... we almost never received a fax- and if we did it was from already established clients who had known the correct number already.
"That's the way to do it" - Punch
Japanese business has avoided the Net because of it's reputation for black had activity. Now that the bad actors like the NSA, the Russians and the Chinese are aware that they now can exploit this avenue, Japanese business is a sitting duck waiting to be shot.
T.38 protocol will encode/decode fax data for transit over an IP network.
Well, if you're out in the woods with no internet connection, no mobile coverage but have two copper wires connected to a telephone exchange, fax can be your saviour.
From a purely technical point of view, if you can manage to connect a fax to those pair of copper wires, that means you can connect to an analog Modem (somewhere between 33 and 56k bits) or an ISDN digital signal (64k), because Fax machines ARE basically modems (pouring data into a printer with only a simple picture compression in the middle).
You could as well wire your copper wire to the appropriate type of modem and do way much more, including PPP to get IP packets.
Maybe not use the modern Web (where every single page seems to need a giant katamari of multi-megabyte disjoint javascript frameworks)
but there could be lots of other low bandwidth possible things beside pushing compressed pictures around.
(text e-mail, connecting to some remote machine with better connection to handle your stuff, etc.)
Basically, a pair of copper wires IS a potential internet connection.
But for the rest, I agree. /. geeks.
doing weird things with a modem on pair of copper wires is something specific to
A fax machine is something that is granpa / granma-proof, because said grand-parents literally already used one in their past jobs before retiring.
Have you tried to enter the E-mail address on the small, resistive touch-screen of a scan-2-mail device?
Yes, did it successfully using a full blown keyboard because said machine accept configuring over a HTTP interface to input presets.
From there, most of interactions a just push 1 or 2 buttons to "mail scan to preset 1" (which is my address, or on some machine could even be an SMB networked share instead of an actual e-mail address), and then all the remaining processing is done from a laptop.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
In most machine the fax side is neatly separated from the network side. So much so that the fax board is optional. Inbound transmissions have some hand shaking which is mostly standard. While some mfg have special modes they mostly all support the same basic modes. The IMAGE data is transmitted and the transmission is closed. The fax image is printed, saved locally, emailed, or possibly saved to the network as an image typically a Tif or PDF. Possibly there is some machine that will ocr a received fax. Could you crash the fax board, probably, with a malformed handshake or image. Your best bet is to include a highly readable link in the fax link so some unsuspecting OCR would pick up the link for some user or application to strangely execute it. I suppose the same goes for barcode.
The kind of people who would be reassured with the legallity surrounding FAX wiretaping, is typically the type of user who has no clue that e-mail encryption *is* a thing, or what the words S/MIME and GPG are.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
However if someone with no tech skills needs to send me a document image it's often far easier to just send a fax rather than spend an hour trying to teach the person to scan, then save in whatever format, and then send via email or other method (if the file is too large for email, often a problem).
Though you can teach them to use an MFP to mail a scan to themselves (basically the same button presses as a sending a fax with a fast-dial number, except that the fast dial-preset point to their own e-mail box instead of another FAX phone number) and then teach them how to forward e-mails with their favorite e-mail client.
The "file too large for e-mail" won't happen that easily, because most MFP will do compression-to-PDF auto-magically usually with better than FAX codecs (though apparently FAX that can handle JPEG and JBIG compression have appeared in the recent decades).
(If the file is too big for a modern mail account, it's also going to take ages of the FAX' slow <64kbits connection).
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Hundreds of dollars just to pay for your semester.
In other saner parts of the world, hundreds of dollars *is* what you pay for the semester.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Is how something like Hylafax or regular old fax machine reacts to these "malformed" fax images.
What this sounds like, is that the printer makers got sloppy in the image rendering end of things and this is some kind of buffer overflow.
No... They wouldn't do THAT.
I've been in the copier, printer, fax business since the early 80's. Most MFP's, for the sake of price, use a software based fax modem. (remember the problems of the old Win modems?) IF that is what they are talking about, I could see where there could be a problem. Most of the higher end machines we sell & service, use a HARDWARE based modem for faxing. The board contains the CML hardware relay, and they even continue to use the dual neon light bulbs, that were there to help drain off any excess AC that may come in over the old POTS copper lines. Most faxing is now down over VoIP, not copper, so they could drop the neon filtering along with the old click bang mechanical relay, but, they still use it. The ASIC on the modem is not an EEPROM, so I don't know how they would hack into that and change it. Like I said, I don't know the entire details, but just from the article, I can see a SOFTWARE based modem getting hacked, but I think it would be MUCH harder to get through a HARDWARE based modem. Also, another point of attack could also be the ATA box connected to the fax, which converts the analog modem data to the digital data required to go out over the VoIP setup. We already in most cases have to turn off the V.34 modems, and slow the modem down to V.17 14.4k or even 9600 to get them to work, even with the T.38 protocol in the ATA box, because they will place them some distance from the MFP, and use unshielded telephone wire to connect and by the time it gets to the fax, the loop current is so low, it sometimes has problems triggering the CML relay! It will be interesting to see if this blows up, like it did about 15 years ago, when that CBS 60 minutes broadcast, showed businesses were trading in old machines and didn't realize they were leaving data on the HDD's they have in them, and most were not encrypted. Now, ever machine we have has ADI self deleting/wiping drives that marry to the machine with a hash code. Not to mention we turn on 128 bit encryption by default with the option of going to 256 bit encryption. All for a flipping copy machine....geez!
Scanning and faxing are the exact same process. Stick paper in select destination.
Any office printer worth a damn will let you pop in an email address instead of a fax number.
1. Take something black, preferably large, and place it on the copier. A t-shirt will work well, but no designs: just solid black.
2. Make four copies of the black.
3. Trim the sheets so they have no white edges or borders.
4. Assemble the 4 sheets together with Scotch tape. Trim off any excess.
5. Apply a strip of Scotch tape to the BACK of the topmost sheet, so it's half on, half off.
6. Dial the target fax machine, then feed the bottom-most sheet into the device.
7. When enough comes out of the bottom, bring it up and apply the bottom to the topmost strip of Scotch tape to create a loop out of the four sheets.
8. Go get some coffee, talk to some co-workers, maybe go to lunch.
Target fax will keep spitting out page after page of black nothing until it either runs out of paper, toner or the fuser burns out.
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governments still use it a lot.
got pulled over by police, my insurance was not valid, the valid paper was at home, i just got it in the mail and didn't put it in my car yet. so the officer asks me - is there somebody at home who can fax it to us.
come again, what? a fax? no, but i can have a picture taken and email it. that wasn't any good, so i ended up having to show the paper at the police station the next day.
other stories are that the fire department needs to get a fax from the mayor to declare certain states of alert. criminals that need to transported, require fax approvals, etc
the list of uses for faxes in the government seems to be endless.
On a long enough timeline, the survival rate for everyone drops to zero.
Good thing we use dedicated fax machines!!
If you or I lived there, we would probably find a modem somehow and also an internet provider that had dial-in lines. Living in the UK, the latter is not the easiest
An actual ISP with dial-in lines would be one possibility.
Another would be remotely connecting to a machine you own somewhere is another possibility, (using this time some normal local number, so get either very low cost or free connection, depending on your phone line plan).
i.e.: be your own ISP.
The E-mail-enabled printers I have worked with were not configured for network setup of scanning to mail* and while many E-mail addresses were stored in memory, subject lines and attachment naming still required the use of the unpleasant touch-screen keyboard.
The idea is to leave the stupid default (e.g.: "SCAN_yyyymmdd.PDF") and mail *yourself* a copy of the document using the 1-button fast-dial.
Then, using your laptop and your favorite e-mail client, forward that e-mail to the final destination while editing the subject line and text body to fit your needs.
Managed to get my parents used to this workflow rather easily.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]