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The “Cobra Effect” that is disabling paste on password fields

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Re: The “Cobra Effect” that is disabling paste on password fields

#382

Earlier quoted context omitted.

On my >10 character passwords (I generally don't use shorter passwords with banking sites, so I don't know how the system behaves for short passwords) they ask for ~11 characters. Of course the login box can, and often ends up, being longer than your actual password, so it doesn't visually reveal the actual character count of your password. In my case they usually end up asking for ~5-7 "real" characters. I presume a…

It's a huge detriment to security. You can break sets of 5-7 characters at a time and combine them instead of having to break the entire password at once.

Seems like a tradeoff. What's more likely - that a bank loses its password database, or that some customers find themselves infected with keyloggers?

Also in any bank that's even remotely sane this is just one leg of a 2FA; often a kind of a "delayed" 2FA - where one factor is enough to get you mostly "read-only" access, and any important changes or wiring actual money requires one-time SMS codes.

Re: The “Cobra Effect” that is disabling paste on password fields

#383
post #297

Earlier quoted context omitted.

then you know that your passwords aren't hashed on their servers This is the immediate alarm that went off in my head reading about this. I've never seen this before either and it sounds like an idea from someone who means well but doesn't understand what they are doing.

They could hash each combination. Probably reduces security, but not a dead giveaway.

Yep, I think this is what happens.

Re: The “Cobra Effect” that is disabling paste on password fields

#384

There is a piece of terrible, unwarranted analysis in this article: > But there’s one angle to this that helps explain the madness and it goes back to that earlier PayPal screen grab. This was of the change password page, not the login page. You can easily paste into the login page and in fact you can even paste into the original password field on the change password page, just not the new password field or the other…

The typo is the added security.

All joking aside, that's why you have password reset functionality. The reason I can't paste in most cases makes me choose another site. One that takes my security seriously. I'm the kind of user that wants to paste in a 40 character long password and store it in a manager that will allow me to forget all my passwords except one or two.

Re: The “Cobra Effect” that is disabling paste on password fields

#385

TradeKing went full idiot and disabled entering your password by keyboard completely. They implemented an on-screen keyboard and there's no way to opt out. Their support forum is full of angry customers, people who can't use their screen readers anymore, etc. They argue [1] it's to protect their customers from key loggers. [1]: https://community.tradeking.com/forum/categories/suggestions...

Most of banking software in Korea is doing the same thing. I had to type my password every single time with a randomly arranged keyboard. Eventually I switched to the only bank that didn't do this.

Re: The “Cobra Effect” that is disabling paste on password fields

#386

I doubt that the motivation for preventing paste in a "confirm password" context is to prevent workarounds to character limits. Why does the "confirm password" field exist anyway? It exists to remove the risk of input error. They want to avoid you locking into a mistyped password and not being able to recover. To this end, it makes some sense to prevent copy/paste, as a user may simply copy their mistyped password an…

This raises the interesting question of why we obscure the input when changing passwords. Showing the new password would allow people to check and correct it, so you'd only need one input. Given that the contents of a password input can easily be revealed, the only security obscuring the input provides is from an attacker who can see the screen but not the keyboard, and has no physical access to the device - a pretty…

I think the original intent of obscuring input password is to counter shoulder surfing.

Re: The “Cobra Effect” that is disabling paste on password fields

#387
post #385

TradeKing went full idiot and disabled entering your password by keyboard completely. They implemented an on-screen keyboard and there's no way to opt out. Their support forum is full of angry customers, people who can't use their screen readers anymore, etc. They argue [1] it's to protect their customers from key loggers. [1]: https://community.tradeking.com/forum/categories/suggestions...

Most of banking software in Korea is doing the same thing. I had to type my password every single time with a randomly arranged keyboard. Eventually I switched to the only bank that didn't do this.

Living here: Which?

Re: The “Cobra Effect” that is disabling paste on password fields

#389

Earlier quoted context omitted.

Isn't that vulnerable to MITM attacks for GSM? There have been quite a few demonstrated at DEFCON that could work very well for attacking this kind of system (on a large scale)

Yes, and not only MITM, but IRL impersonation attacks; Wired published an article about it today: https://www.wired.com/2016/06/hey-stop-using-texts-two-facto... Attackers convinced (either with their official badges or by conning) the targets' cell service providers to change the SIM info associated with the accounts, and thereby intercepted SMS authentication codes.

You are confusing this method with one time SMS. This isn't SMS, it uses the Javacard-based SIM toolkit to decrypt a challenge sent to to the mobile number. the passcode for decryption is usually a 4 or 6 character PIN number. For an attacker to MITM this he would have to both have the number assigned to his own SIM and he would also have to impersonate the victim an show up in person to a bank or a security apparatus and social engineer his way so they program the new SIM with his personal PIN. a bit harder that just calling up the service provider to say 'I lost my mobile phone, i have this extra SIM card laying around, can you assign my number to that?'

Re: The “Cobra Effect” that is disabling paste on password fields

#390

Earlier quoted context omitted.

> consists of our birthday + 4 digits What if you have more than 10,000 people who have the same birthday? Let alone people with similar birthplaces/gender/etc. If that's all there is to it it seems like you'd run up against a combinatorical ceiling pretty soon.

There will never be a problem with that in Sweden. They're averaging 328 births per day. They'd need to increase their population from 10 million to the size of the United States to bump up against that limit. Sweden has added two million people in the last half century. In net terms, essentially all of those two million have been immigrants rather than born in Sweden. They're de-populating when you exclude immigrati…

Actually, it already is a problem. According to this article, around 2,500 people have been assigned a personal number which differs from their birthdate. [1]

The last digit is just a checksum digit, so we're left with 3 digits per day. But that still would give some leeway for each day. The problem seems to be that some immigrants have been assigned a default birth date (Jan 1 and Jul 1) as their exact birth date is unknown.

Another issue which is not mentioned in the article is that we're only using two digits to encode the year (i.e. YYMMDD-XXXX), which causes problems now that many live to be 100+ years. Most banks and other places now requires you to enter a four digit year, even though that technically is incorrect. The correct way to annotate that someone is over a hundred years old is that the dash changes to a plus sign (i.e. YYMMDD+XXXX), although I've never seen that implemented anywhere.

[1] https://translate.google.com/translate?sl=sv&tl=en&js=y&prev...

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