[HN Gopher] The 74,000 numbers of Barclays Bank
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The 74,000 numbers of Barclays Bank
Author : kristianp
Score : 76 points
Date : 2021-08-27 10:16 UTC (2 days ago)
(HTM) web link (shkspr.mobi)
(TXT) w3m dump (shkspr.mobi)
| notatoad wrote:
| it seems to me that a 1.3MB file is a perfectly reasonable size
| to include in a webpage, and much better than a regex for this
| purpose - a file containing numbers is maintainable without
| having to also maintain a test suite to ensure that your regex is
| still valid every time the company is assigned a new phone
| number.
|
| maybe a server-side lookup would have been a little bit nicer
| than shipping the whole list to the client side, but a static
| client-side app can be stored in the CDN layer, doesn't require
| provisioning any server resources, and sidesteps any security
| concerns about servers processing user input.
|
| it would have been nice if they'd cleaned up the user input
| before querying the dataset, but overall this looks like a clever
| solution to release a feature with the smallest risk and
| maintenance profile possible.
| matthewmacleod wrote:
| I agree that this approach is actually pretty reasonable for
| checking if a specific string is in a relatively small list of
| possible values that can't easily be expressed as a simple set
| of prefixes or whatever. It's must simpler and easier to
| maintain.
|
| The bigger problem with this approach is that it exposes a
| canonical list of phone numbers that are guaranteed to not be
| flagged as fake by the tool itself. That isn't likely to be a
| _massive_ concern here specifically, since it will always be
| easy to find a valid customer service number without that
| access. But I'd expect a team looking at dealing with fraud or
| scams to be pretty conservative about information disclosure
| generally - it would be a good argument to implement this as a
| backend service.
| james_in_the_uk wrote:
| In banking, any dislcosure of info hitherto not public is a
| /potential/ new attack vector for fraudsters. Surprising that
| they did it this way
| jlg23 wrote:
| That is a fine tradeoff until you realize that a _single_ ,
| manual verification of these 1.3MB telephone numbers costs more
| than developing and maintaining the unit tests...
| tedunangst wrote:
| Who verifies the unit tests match the real phone numbers?
| andy_ppp wrote:
| I think with gzip how much is the total < 100kb?
| Recursing wrote:
| https://www.barclays.co.uk/content/dam/json-
| files/TelephoneN... I see 190kb transferred in chrome dev
| tools.
|
| I fully agree that the criticism in the article is not
| warranted
| bellyfullofbac wrote:
| How about the cricitism of the tool not caring about +44 or
| non-numeric characters?
|
| It's still lazy programming...
| ljm wrote:
| I'm struggling to see how a regex would work, either. It's a
| database lookup, a regex that matches only 74k numbers out of
| every possible valid phone number in the UK would be absurd.
| staz wrote:
| I think the intuition is that a lot of these phone number
| come in ranges, so it would not be a regex but multiples? But
| yeah seems easier to just encode the ranges, than some
| complex system to create the most minimal regex.
|
| edit: checked the comments of the original post and they
| apparently used perl to produce a 11kb regex.
| scrollaway wrote:
| Several years ago, along with some cofounders, i created a
| Hearthstone website / database (hsreplay.net). If you look at
| the card database it's incredibly fast once loaded because all
| the filtering and displaying etc happens clientside. It
| downloads a 25-something megabyte JSON (which compresses
| extremely well), cf. hearthstonejson.com.
|
| Downloading a big JSON file locally is underrated. I
| implemented the exact same strategy on https://overframe.gg, a
| Warframe database. It allows a fantastic user experience ...
| the tradeoff being the slow loading time (which is invisible to
| most people on good connections).
|
| Overframe was a SPA though and had to lose the approach on most
| pages because of SEO. The usage were too different. Before that
| every single page on the site was clientside and available
| immediately after initial load.
|
| For a tool though, especially one that relies on user input
| (and thus will load in the background before your user starts
| interacting with it), it's a great approach as long as your
| data is somewhat bounded.
| 1123581321 wrote:
| Agreed. I've written a lot of B2B tools and locally storing a
| copy of lookup data is perfect when appropriate due to the
| generally smaller dataset sizes.
|
| Back in the day I'd even do super fast geo proximity locally
| by including a json of the locations of first three digits of
| zip codes and truncating the zip code of the user to make the
| comparison.
| aftbit wrote:
| Oh hey you made Overframe? Thanks for that! I had that open
| for at least a few minutes every day for about six months
| during the pandemic.
| scrollaway wrote:
| Couldn't have done it without Semlar, the current
| maintainer (fun fact, i never played Warframe, this was a
| job for a client/friend). Glad it's of use to you!
| wwwaldo wrote:
| Wouldn't it be better to perform a server side lookup to avoid
| leaking the full list of currently used Barclays numbers in
| plaintext to fraudsters?
|
| The fact that there isn't any user input sanitization makes me
| inclined to believe that this implementation decision may not
| have been well-thought-out (which I'm guessing was the author's
| point exactly)
| code_duck wrote:
| that is mentioned at the end of the article.
|
| >why not POST the number to a service which can be updated?
| notatoad wrote:
| when you're offering a service designed to expose a list of
| numbers, there's no way to design it in a way that doesn't
| expose that list of numbers. given enough time, a motivated
| person _will_ extract all the data.
|
| most likely, this page started out as a list of all 74k phone
| numbers, and at some point somebody built a lookup tool on
| top of it. there's no reason to assume that keeping the full
| list secret was ever a design goal.
| mnd999 wrote:
| Sure, but Barclays made it trivial.
| edent wrote:
| I guess you don't pay per MB for data? Or live in an area with
| poor connectivity?
|
| Making life easy for a web developer, rather than saving time
| and money for users, is unethical behaviour. The developers are
| putting their (and their company's) comfort over that of the
| people using their system.
|
| Perhaps that's OK on a day-to-day basis. But this is a system
| designed to help people in a stressful situation trying to
| ascertain if a caller is genuine. That's not a situation where
| you want to needlessly pipe a couple of hundred KB over a dodgy
| 3G connection.
| Retric wrote:
| It's only 191 kB compressed, which seems like a reasonable
| thing to send over even a dodgy 3G connection. Not that I
| think it's a good idea, but in terms of bank IT I've seen far
| worse.
| vmception wrote:
| The only thing they lose is a few points on a website
| benchmarker
| [deleted]
| playpause wrote:
| You have no real idea of the various numbers involved or the
| ins and outs of the decision, so to accuse people you don't
| know of "unethical behaviour" is ridiculous. Get over
| yourself.
| mrb wrote:
| Agreed, this 1.3 MB JSON data file is perfectly reasonable: it
| compresses to only 191 kB in the HTTP response with standard
| gzip compression that all browsers have been supporting in the
| last 20 years (I just checked with Chrome's dev tools)
| vmception wrote:
| > Because no one knows how to build a sensible web service any
| more, the page loads a 1.3MB JSON file containing every number
| that Barclays has.
|
| Banks never did. This is par for course. Just be lucky they
| didn't send it in FIX, because you know a bald guy clinging to
| their 2010 Blackberry "because of the keyboard and emails" really
| wanted to send they payload over the FIX protocol
| mathattack wrote:
| Bank IT departments are filled with stats, Econ and financial
| math majors who couldn't get front office jobs after school.
| They're great for creating software that prices derivatives, but
| awful for reliability, security and all things engineering.
| Meanwhile, the decision makers just use Excel for all the
| important things. Things blow up all the time, it's just that it
| rarely gets public. For whatever reason $200mm in wasted IT
| doesn't generate the headlines like a $200mm trading mistake.
| tyingq wrote:
| If you sort the numbers, then represent them as the amount you
| need to add to the prior number[1], it produces a very small file
| once compressed...about 4k[2].
|
| So, even with the code to turn it back into a list, handle the
| leading zeros on many numbers, etc, it would be under 10k total,
| much smaller than the crazy regex.
|
| Not general purpose, and a bit silly, but you can get the list
| pretty damn small.
|
| [1] Like: "1234, 1235, 1435: becomes "1234, 1, 200"
|
| [2] The < 4k gz file that you can reproduce most of the list
| from:
| https://github.com/tyingq/barclays/blob/main/out.c.gz?raw=tr...
| Gunzip, then read each line, then add the prior read line to it,
| prepend a leading zero and print. "Prior read line" is 0 for the
| first line. There's a small amount of the list you would have to
| hardcode or handle another way...the numbers without leading
| zeros, total of 63 numbers.
| gruez wrote:
| > If you sort the numbers, then represent them as the amount
| you need to add to the prior number[1], it produces a very
| small file once compressed...about 4k[2].
|
| That seems like a nightmare to do searches on. I'd probably
| compress it with a prefix tree or similar. In terms of off the
| shelf solutions, sorting the list, saving as a newline
| delimited text file, and then compressing with LZMA2 gets you
| down to 22KB.
| baobabKoodaa wrote:
| You don't need to do searches on the compressed JSON, you can
| uncompress it in memory in client-side to do searches.
| nerdponx wrote:
| The point is that they didn't think to do this or anything else
| to try to keep the bandwidth down, while still managing to
| deliver a lazy sloppy product that doesn't work very well for
| its sole purpose.
| tyingq wrote:
| Sure. It just made me curious what you could do.
|
| Also, there are a fair number of duplicates in Barclay's
| original list, so it's even more lazy an effort than that :)
| snet0 wrote:
| I don't even know if this qualifies as a lazy effort, as
| that implies _some_ effort was put in. This was an effort-
| free implementation. The user, as usual, pays the price.
| kccqzy wrote:
| Google uses a similar scheme of compression in their Safe
| Browsing v4 protocol: https://developers.google.com/safe-
| browsing/v4/compression It calculates deltas (adjacent
| difference) between a sorted set of numbers and then use Golomb
| encoding on that.
| philjohn wrote:
| Barclays have a decent mobile app, and you can call them directly
| there (even a video call).
|
| As far as UK banks go, they're one of the more secure ones -
| giving you out a pinsentry 2FA device for accessing your account,
| setting up new payee's etc.
| trebligdivad wrote:
| While the 74k number looks insane, what I think they have is some
| centrally allocated PBX block or two, and then a handful of
| numbers for each branch, of which they have a few thousand; so it
| looks a little less crazy.
| idiotsatbarclay wrote:
| These are the people protecting people's money, wow.
| carnitine wrote:
| Was it really worth making an account for this?
| toyg wrote:
| You misunderstand the role of modern banks: they're not there
| to protect your money, they exist to _create money_ through
| credit. Everything else (payment routing and account
| management) is just an accessory, a necessary evil. They want
| your money in "safe" accounts only because the law forces them
| to keep around a certain amount of cash in case all that credit
| turns bad.
| baobabKoodaa wrote:
| It seems that you have misunderstood how banks create money
| through credit. Even if there was absolutely no requirement
| to keep a certain amount of cash, banks still couldn't create
| infinite money out of thin air, because that's not how it
| works. I wrote more about this here:
| https://www.attejuvonen.fi/money-out-of-thin-air/
| kqr wrote:
| This is correct. One of the early and still accessible
| references is Bagehot's _Lombard Street_.
| dredmorbius wrote:
| _Lombard Street_ by Walter Bagehot
|
| https://archive.org/details/in.ernet.dli.2015.276712
|
| https://en.wikipedia.org/wiki/Lombard_Street:_A_Description
| _...
| incone123 wrote:
| I worked in a place that did this on an internal page, but with
| all the budget codes, financial limits and which manager they
| belonged to. I don't know if it posed a fraud risk but if there
| was none then they could have just stuck an Excel file on
| SharePoint.
| gojomo wrote:
| "Forget it, Jake. It's Bankertown."
| dredmorbius wrote:
| For those missing the reference:
|
| https://yewtu.be/watch?v=TjSshSvQWQA
| actually_a_dog wrote:
| So far, everyone is focusing on the JSON vs regex thing, but
| that's not the worst of the criticisms leveled here. Not being
| able to use the +44 prefix, or format the number with dashes are
| stunningly obvious usability problems that honestly should not
| have made it out of QA.
|
| You'll see the same thing on different sites with credit card
| numbers. See, every credit card issuer uses a scheme called an
| "issuer identification number" to tell you what type of card it
| is. And, there's a list of them [0]. So, for instance, I can tell
| that any valid credit card number that starts with 4 must be a
| Visa. So, why ask me what type of card it is, when you can figure
| it out yourself?
|
| Those rare sites where you actually want to put your Social
| Security number in have these sorts of issues, too. Some of them
| require dashes, some of them don't. Some of them will only allow
| you to enter 9 characters, but won't tell you not to use dashes.
| It's infuriating, really. And, any site where you enter an
| account number can potentially have these types of issues.
|
| It's not like being just a little more flexible with input
| formatting is a major feature with huge implementation costs and
| security risks, either. We're talking about failing to take a few
| minutes' thought in order to be a little more kind to the user,
| and that's just inexcusable, IMO.
|
| ---
|
| [0]:
| https://stevemorse.org/ssn/List_of_Bank_Identification_Numbe...
| Dunedan wrote:
| > It's not like being just a little more flexible with input
| formatting is a major feature with huge implementation costs
| and security risks, either.
|
| Just in case somebody considers implementing phone number
| parsing and normalizing: Just don't and use Googles
| libphonenumber, which offers solid, ready to use
| implementations in various languages (there also exist ports
| for other languages too):
| https://github.com/google/libphonenumber/
| hallway_monitor wrote:
| In case anyone asks you to implement any input formatting,
| see if you can get them to change their minds. IMO the most
| bug-prone and useless feature of websites. Let the user put
| in whatever they want and just input.replace(/[^0-9]+/, '').
| You, your users and your product owners will be happier.
| CraigJPerry wrote:
| From a UX point of view, what would be the downsides of just
| rendering a plain text file of 1 number per line in alphanumeric
| order?
|
| Does this really need any more UI than the browser's chrome?
|
| Not every web user knows "ctrl+f" or "find in page" on their
| phone, but those that don't, do still know how to scroll 74,000
| lines of ordered numbers (which is surprisingly easy and fast - i
| just tried scrolling 74k lines in excel on mobile).
|
| The one use case i'm thinking might be confounded is a screen
| reader for the visually impaired or blind but even then, i'm
| thinking this use case is probably covered?
| ghusbands wrote:
| The typical user, faced with a huge sorted list of phone
| numbers and asked to just look through it, will not know how to
| find a number of interest and will quite possibly be quite
| flustered or irritated.
|
| It's not technologically hard to implement a search, so I don't
| see a reason to only show a big list.
|
| Having all the numbers visible in the page would certainly help
| it show up in web-search results for those phone numbers,
| though.
| dredmorbius wrote:
| True.
|
| Overassessment of general _literacy_ (the reading kind, not
| computer or maths literacy) is exceedingly common in
| technical fields. Averag computer skills are abysmal.
|
| About 5% of computer users have "advanced" literacy, defined
| as "Some navigation across pages and applications is required
| to solve the problem. The use of tools (e.g. a sort function)
| is required to make progress towards the solution. The task
| may involve multiple steps and operators. The goal of the
| problem may have to be defined by the respondent, and the
| criteria to be met may or may not be explicit"
|
| Scheduling a meeting room, or determining "what percentage of
| the emails sent by John Smith last month were about
| sustainability" are examples of level-3 tasks.
|
| _A quarter of the adult population cannot use computers at
| all_ , 14% are at "below level-1" skills, and 30% can only
| perform very basic level-1 tasks, for a total of _70% of the
| population which has only very basic skills ... or less._
|
| It's easy to over-estimate the general literacy and numeracy
| of the population, especially if you yourself are college-
| educated and work in and/or with information technology.
|
| The United States performs one of the most comprehensive
| assessments of adult literacy. *The key lesson for me is just
| how limited it is.*
|
| https://nces.ed.gov/pubs2019/2019179/index.asp
|
| The findings correspond highly to a study of adult _computer_
| literacy amongst 20 countries by the OECD:
|
| "Skills Matter: Further Results from the Survey of Adult
| Skills" http://dx.doi.org/10.1787/9789264258051-en
|
| Computer usability expert Jacob Nielsen has a discussion of
| this as well: https://www.nngroup.com/articles/computer-
| skill-levels/
|
| I've discussed this as "The Tyranny of the Minimum Viable
| User", which both notes that much of the population has very
| basic skills, and that this _also_ hampers the very small
| minority who do.
|
| https://old.reddit.com/r/dredmorbius/comments/69wk8y/the_tyr.
| ..
| hallway_monitor wrote:
| I made an unrequested but useful internal web app recently and
| added a 'Search' link. Clicking the link popped dialog that
| said 'Press Control-F to search'
| danuker wrote:
| I imagine once you get a bug report for the search feature,
| it's going to be hard to fix :)
| orf wrote:
| > From a UX point of view, what would be the downsides of just
| rendering a plain text file of 1 number per line in
| alphanumeric order?
|
| It surprises me that you need to ask that
| rhn_mk1 wrote:
| Rendering files megabytes in size is quite bad in a browser.
| I'm not sure of the reason, but it fires up slowly, and I
| suspect memory usage is also quite bad.
| thaumasiotes wrote:
| > and I suspect memory usage is also quite bad.
|
| For a text file? Why?? Wouldn't the worst case be the size of
| the file?
| rhn_mk1 wrote:
| The browser isn't optimized for text files though, but for
| documents and applications. I've noticed some flickering
| while scrolling longer pages before, and from that I expect
| that there's some caching of the rendered content of the
| page.
|
| The text file also gets transformed into a html document
| with DOM (inspect one in Firefox to see), which likely has
| its own caching tricks for performance.
| surfingdino wrote:
| Having worked on projects related to integration of other systems
| with the banking systems I can confirm a massive lack of skills,
| experience, and imagination amongst developers and managers
| working for banks. They pay hundreds of millions of dollars and
| get very poor return on their investment in IT because they
| themselves have no people working for them who have any idea how
| to build a secure system and the consultancies providing bodies
| have no idea how to build what the client wants. The turf what
| between various consultancies and managers make things even
| worse. The results are mediocre and laughable.
| luckylion wrote:
| I've heard this many times, also directly from a guy I knew
| years ago, so I guess there has to be some truth to it.
|
| What I don't understand is how that comes to be. Are just
| people who are not skilled enough applying to work at a bank?
| Do they have some weird selection criteria that tends to
| discard all the good people?
|
| You'd think that they'd hire some good people by accident and
| those people would be more than capable of running the whole
| operation, but apparently they don't.
| JanisL wrote:
| In my experience of these things the environment at many
| banks greatly reduced the effectiveness of technical software
| staff. For example when I went to do some workshops for a
| bank a while back on data science, half the room didn't have
| their access approved to get the data and a third of the room
| didn't have access to the big data platform and many couldn't
| install any analysis software on their work laptops and it
| had been over 8 weeks since their project started. People who
| are really passionate about technology will find this sort of
| situation quite annoying.
| zkmon wrote:
| Approvals take 6 to 8 months
| lozenge wrote:
| I work at a bank and we could work at the same bank.
| ipaddr wrote:
| Decisions are all top down. Projects are run top down. The
| developer delivers the spec the consultant has approval on.
| Each idea gies through rounds of approvals. Have a great idea
| as a developer? Save it for your next role.
| zkmon wrote:
| Spot on! Also many projects end after achieving the main
| goal - a powerpoint slide deck, claiming something was
| done. No one has ability to ask what was done and why it
| was done. Also the same project is reworked multiple times,
| during dev stage, over multiple years as the tech becomes
| old or other dependencies change.
| aoms wrote:
| This
| [deleted]
| puppet-master wrote:
| 187k of very compressible strings, producing a small array in
| memory, in exchange for avoiding all the costs of a web service
| seems like an excellent trade off.
|
| 187k seemed quite expensive, the file actually drops to 49k with
| Brotli and removing whitespace.
|
| Sorry if this put a backend team out of a job, but I definitely
| approve of this design. The other number normalization defects
| could just as easily be fixed client-side
| reedf1 wrote:
| And for the scammer - a great list of phone numbers to spoof!
| ihaveajob wrote:
| This is the relevant complaint. Not that scammers need much
| help collecting a list of legit numbers to spoof, but now they
| can tell their victim to go and check the origin number on this
| service and falsely reassuring them.
| throw0101a wrote:
| > _But how can you be sure the number displayed on your screen in
| genuine? You can 't. The telecom system is hopelessly insecure
| and shouldn't be trusted for anything more complicated than
| dialling the speaking clock._
|
| There is a (set of) protocol for signing telco connections that
| was developed:
|
| * https://en.wikipedia.org/wiki/STIR/SHAKEN
|
| * https://www.fcc.gov/call-authentication
|
| Anyone in the telco space that can comment on how much this is
| implemented in their geographic area (US, EU, APAC, etc)?
| ThePadawan wrote:
| A few years back, I wanted to refactor something in the quite
| large codebase I was working on at the time.
|
| I stumbled on a class that was very short and simple. If you know
| enterprise code, that should immediately make alarm bells ring.
|
| And yes, indeed, all this code did was provide a (world-visible)
| API endpoint which returned the result of "SELECT id FROM <table
| with millions of rows>" as a JSON array of numbers.
|
| IIRC it was used for something theoretically reasonable like
| "figure out if this search index contains all rows from that
| table".
|
| But I'm sure there were less hacky ways to achieve the same
| result. Maybe even put permissions or firewalls on it.
| politelemon wrote:
| Along similar lines, I once found a very simple class. It was
| an endpoint which executed a stored procedure. The name of the
| stored procedure was passed in as a query string parameter.
| There was no validation being done. It also ran system stored
| procedures; if you're not familiar with that, think admin and
| housekeeping type functions on the database.
|
| We couldn't immediately disable or firewall it as it had
| embedded its roots deep, and a lot of things calling it didn't
| know they were calling it.
| Dunedan wrote:
| > Because no one knows how to build a sensible web service any
| more, the page loads a 1.3MB JSON file containing every number
| that Barclays has.
|
| While other comments have already mentioned that it's actually
| "only" ~190kB which get transferred thanks to gzip compression,
| there is still a lot of potential for a smaller transfer size by
| simply using brotli instead of gzip for compression. With brotli
| the size of this file is <60KB, so only less than a third of the
| file size of the gzipped data.
|
| Using brotli would be an easy win and improve performance of
| loading all other assets as well, without the need to change
| anything in the actual implementation of the website, however
| Barclays Bank is probably still running a webserver stack which
| doesn't support brotli yet.
| asperous wrote:
| The file is transferred compressed with http gzip so only 190kb
| is transferred.
|
| I can see the point of being efficient but this doesn't seem that
| bad all things considered. At least the list is also human
| readable unlike a regex or custom compression.
| zimpenfish wrote:
| I tested the 44k optimised Perl regexp but it seemed to let
| through some other stuff - i.e. replacing the leading 0 with 8
| allowed through a bunch of numbers that aren't on the original
| list.
|
| e.g. changing 02071160299 to 82071160299 still appears to pass
| the regexp.
| Recursing wrote:
| https://shkspr.mobi/blog/2021/05/the-74000-numbers-of-barcla...
| it's mentioned in another comment that indeed they forgot the
| anchors
|
| The "correct" regex is 11KB and can be found here
| https://gist.github.com/jes/e678e4300d1cfcbcc12b46aaa7e58e30
|
| I agree with another comment here that the 1.3MB JSON is a
| better solution though
| ahmedfromtunis wrote:
| I'm sure that this regex wasn't manually created. Is there a
| service or tool to create such regex?
| philjohn wrote:
| You can go a long way by building a Trie and walking it to
| autogenerate a regex, although optimising it is a more
| complex challenge.
| Recursing wrote:
| Indeed, here is the source from the linked comment https://
| gist.github.com/jes/c7b848220bc36d8ae3771cd77f232d0c
| zamadatix wrote:
| Probably the cardinal sin of regex: forgetting the anchors.
|
| Also something really weird: when I view zimpenfish's comment
| in the post it shows as 54 minutes old which makes sense, when
| I click it to view direct or reply it shows as 2 days old which
| is really wonky. Any idea what is going on there?
| https://i.imgur.com/DvBDcIL.png
| skinkestek wrote:
| That's funny...
|
| Might be something that got resubmitted from the second
| chance pool and then automatical rewrite only did half the
| work it should or something is cached or something similar?
| zamadatix wrote:
| Oooh, I bet you're right!
| detaro wrote:
| AFAIK dang said that's intentional. The view on the thread
| gets faked to look consistent, but they don't want to
| modify the actual metadata of the comment you see in the
| direct view, and something is always going to be "wrong"
| however you do it.
| ajuc wrote:
| Just make it accept a number and return true if it's valid.
| Nobody's going to ask for 1000 numbers, and if they want to DDOS
| they can do it anyway.
|
| And if for some reason you can't - please don't return your data
| in a proprietary format based on a clever hack. Just use gzip.
| barbazoo wrote:
| This website and the one they're referencing shouldn't even
| exist. Barklays' website should just tell the customer to always
| call them back. Spoofing the phone number isn't just a
| possibility, it's normalcy.
| carnitine wrote:
| The website allows them to check a number and then manually
| call it. How does spoofing interfere in that case?
| r1ch wrote:
| It gives a false sense of security. The vast majority of
| users do not understand phone numbers can be spoofed, and
| will use this website to check if a call they received is
| from a "legitimate" number, instructions be damned. It
| wouldn't surprise me if scammers even incorporate it into
| their routines.
| vlovich123 wrote:
| The bank could easily record whether or not they are in
| contact with the customer over the phone when they initiate
| outreach. Then standard practice would be "visit Barclays
| and enter your phone number to check the call is legitimate
| and get the name of the agent " or more realistically even
| a push notification in app. Asking people to call back is a
| canonical example of bad UX in the name of security that
| weakens overall security (like stupid password
| requirements, rotation requirements, etc).
|
| It can take ages to get through back to an agent and it may
| not even be the same one or even in the same department.
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