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Questions tagged [one-time-password]

One-time password (OTP) protocols and implementations (software and hardware)

0
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0answers
49 views

Storing TOTP codes on a Feiteian ePass FIDO key

I'm looking for some Android apps that can store / read TOTP codes off of a Feitian ePass FIDO key using NFC. There appears to be a fairly simple way with a yubico key / and key but I don't know how ...
0
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1answer
135 views

Which is more secure Yubikey + Keepass using Challenge/Response or Yubikey + Keepass using OTP?

I use a Windows 10 PC and an Android phone with Keepass. I would like to add a second factor on top of my master password that works with both Windows 10 and my Android phone. Between the two ...
2
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2answers
106 views

Is stand-alone one-time password less secure than OTP + traditional password auth?

I have a client that would like to use one-time passwords (via SMS or Email) for their app, and their requirements spec does not include traditional password-based authentication. I haven't seen this ...
4
votes
2answers
176 views

Telegram (or other messenger) message as second factor in 2FA

Is it safe to send code via messenger bot and use it as second factor in auth? The scheme looks like the same as SMS one. A user opens application or look at a push notification and use the code. Why ...
2
votes
1answer
69 views

Security implications of auto-submitting OTP?

So the question was originally asked as a part of the UX question here. My question is that, Are there any security risks involved when I auto-submit the OTP? Currently, I'm limiting the number of ...
3
votes
3answers
464 views

Bank sends one-time password by e-mail (while sending on SMS) for transaction verification; is this insecure?

Most of the banks uses OTP (One Time Password) to enrich the authentication through dual factor. But I observed Banks are sending the OTP to mobile as well as email. I suppose sharing passwords on ...
1
vote
1answer
70 views

Is it safe to receive (One Time Password) OTP to the Mobile where the online banking application is installed?

Assume a customer of a bank is using online banking facility and he is using an online banking application on mobile (android). There could be a possibility that particular mobile could be ...
3
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2answers
211 views

Do all Authenticator Apps use the same algorithm?

I've tried some Authenticator Apps (Google,Microsoft,Authy,Lastpass,...) and all of those apps generate same one time passwords at the same time ? So, these apps are use the same algorithm which is a ...
0
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1answer
32 views

Will evolving bio metric capabilities on mobiles replaces online transaction verification through SMS (OTP)?

We are working on an online eCommerce site and we need to have online transactions. The common mechanism of verifying the online transaction seems the OTP (one Time Passwords) over SMS. But this ...
1
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1answer
174 views

Best practices to protect public/private SSH key pair in web interface?

I've got a dilemma here: I'm working on a system that will connect to remote linux servers for monitoring and automating some processes. Since user+pass is insecure for obvious reasons and public/...
0
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1answer
161 views

What should be the life time for SMS OTP?

I've tried to find such a standard that mention the lifetime of SME OTP, however, NIST is no longer recommended using SMS OTP due to the risk involved. Regardless of the security concerns, I still ...
7
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1answer
185 views

Why use one-time codes for two-factor authentication backups?

I am building an web application that uses two-factor authentication. While implementing the recovery feature, I see that most companies (eg Apple, Facebook, Github) provide a set of ~15 backup codes,...
1
vote
1answer
138 views

SMS OTP as 2FA - should there be sms session id in sms for user's verification?

Several times I saw SMS 2FA implementation when a web site shows "sms session id" (say, 8 digits token) right after sending sms to user together with OTP prompt. Sms comes with OTP (say, 4 digits) and ...
1
vote
1answer
119 views

Should I reply to an email saying that I requested online access to a website?

I received an email saying I requested access to a website. The email also includes a one-time passcode. I did not do anything that would require a one-time passcode. At the bottom of the email is a ...
0
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2answers
322 views

OTP generation is specific to SIM or Phone number

Are the messages including OTP sent to a mobile phone addressed to the SIM card or the phone number? If I decide to have a new phone number and the old phone number is allotted to a new customer, the ...
2
votes
4answers
354 views

Does a two-factor authentication dongle (OTP) which is always inserted in MacBook add a security benefit?

I think to get a Yubikey and read that Keepass with OTP makes no sense No. Security remains the same + extra cognitive overhead. I try to store all data local and use seldom cloud based services. If ...
0
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1answer
1k views

Why is the need to expire OTP?

OTP can be implemented either using Google Authenticator or by sending SMS to the user. The GA code is created using a timestamp and the code expires if it's used after some time. However, in case of ...
9
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4answers
928 views

Prevent against OTP abuse in app sign up flow

This may sound like an open ended question, but I would like to take my chances and understand if there is any way the rest of the community is handling this issue. Let's say there is an app that ...
1
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4answers
247 views

Why do (many) TOTP devices or TFA apps use none or simple access password?

In Sweden, where I live, you can use an app called BankID to identify yourself and sign into official website or sign up official documents. The app uses a 6 digits (numerals, not alphabet or symbols) ...
0
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1answer
134 views

Windows Server more vulnerable for password extraction during shutdown?

Is a Windows Server (e.g. Windows Server 2008) more vulnerable during the shutdown process compared to the Server is up and running? Does the process of shutting down Windows introduce additional ...
2
votes
2answers
180 views

Web Application Using Identity Federation & OTP

We are running a web application using a client's identity federation to authenticate users. A new requirement is to use 2FA, we have decided to use an OTP algorithm using Java, similar to this one ...
3
votes
1answer
118 views

Is my authentication method secure?

I have built a web-facing tool which is mostly for internal use, but some of our clients will also make use of it. When building the registration/login parts I had a thought about who would be using ...
0
votes
1answer
102 views

How can the german ChipTAN / CardTAN system be secure?

The german ChipTAN (https://en.wikipedia.org/wiki/Transaction_authentication_number#ChipTAN_/_CardTAN) system calculates a TAN that is send to the banking server to proof the transaction. The number ...
5
votes
1answer
257 views

Yubikey Desktop Authenticator

Would you say it is more secure to use Yubikey Desktop Authenticator than Google Authenticator? Instead of using Google Authenticator every time I want to login to some site I am wondering if it ...
19
votes
4answers
3k views

How secure are password managers with account recovery?

The major commercial password manager companies claim to have a "zero knowledge" system. This means the master password of the user is the only way to decrypt the data and it's is not stored anywhere. ...
30
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2answers
6k views

Is emailing sign in links bad practice?

In my Spring application, I was planning to remove passwords from the authentication process by sending a "magic sign-in link" to a user's email address. However, in this question Rob Winch (lead of ...
3
votes
1answer
99 views

Having sudo mode in a web application, why use a password instead of one time passwords?

Online services, like GitHub, have Sudo mode. Sudo mode means, that a user performing delicate actions has only to authenticate every couple of minutes, but than again, although they are already ...
1
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4answers
178 views

Aren't the current implementations for multi-factor authentication heavily dependent on a single point of failure?

A lot of 2-factor authentication methods seem to rely on either a text message, email or a one-time password like Google's Authenticator as the second step in authentication. It seems like these ...
0
votes
1answer
103 views

Why send multiple codes and ask the user to input only one?

Consider the following (real-world) scenario: When making a credit/debit card purchase online, the bank sends an SMS containing 4 different numbered “passwords” and then prompts the user to enter a ...
2
votes
4answers
2k views

Best practices for storing 2FA recovery codes

I’ve recently started using 2FA on a bunch of services and I’m not sure how to best store the recovery codes. I can think of 3 options: In a secure note on LastPass In a Dropbox folder On a usb stick ...
-1
votes
1answer
617 views

Send hash password or send password to hash in server? [duplicate]

Im doing a little research in my question but no found any concrete answer. I have a client-server architecture. Im using Bcrypt as hash function (the password its store as double hash), and HTTPS to ...
0
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2answers
217 views

Is this passwordless authentification system is less secure than big websites authentifications?

I develop a web and mobile Application, managed by my REST API server (SSL with Strict-Transport-Security enabled). I don't believe anymore in the classic login/password authentification method (1)(2)(...
3
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1answer
1k views

Best practices for generating and using random timed OTP

Suppose I want to implement an OTP system that generates 6 to 10 digit numbers. (assume its used for reset password, or send money) The OTPs have an expiry time, so they keep getting removed from the ...
0
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2answers
207 views

Is Password Less Login mainstream? What sites are using Password Less Login? [closed]

Looks like GE's FirstBuild community site is using Password Less Login pattern. For Login, they just email a custom temporary PIN to a registered email address I am curious which other popular sites ...
0
votes
1answer
73 views

Which approach provides more authenticity of image ownership: cropping, or reduced resolution?

Even if this particular approach likely provides medium to low assurance, which approach is more trustworthy: Suppose I take a set of photos that I own, and crop all of them after I magnified by 25%....
1
vote
3answers
466 views

Prevention of devices using same OTP secret

I have a requirement of OTP applications on mobile devices not sharing the same secret (even if the mobile devices are owned by the same user). A single secret must be present in a single device. ...
3
votes
1answer
5k views

Why doesn't KeePass use two factor / one time password generation to protect the database?

I've read KeePass kinda sorta tries as much as is possible to limit keyloggers (at least on PC). But since you type in your master database password on many devices many times, there's a huge chance ...
0
votes
1answer
135 views

Secure email hosting service for a law firm [closed]

I am looking for an email hosting service for a small law firm (4-5 accounts). What i am looking for is: Possibility of sending password (or question/answer) encrypted message to a user outside of my ...
7
votes
2answers
1k views

Is accepting the current and the previous one-time password a bad practice?

I often see two-factor authentication (2FA) methods using one-time passwords (OTP) implementations wherein the current (previous) and sometimes even 2 or 3 previous tokens are still valid. This is ...
1
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1answer
428 views

One-Time-Password securing an embedded server via OpenSSL

I am developing an application to secure communications between a client and an embedded linux server. I am very new to the field of cryptography, so at this stage I am looking more for guidance - ...
1
vote
1answer
100 views

inherent drawbacks of browser based OTP solutions?

We already have two sorts of OTP generators in place: (a) as hardware (token) (b) as software (e.g. Google authenticator, RedHats freeOTP) Now I saw browser based solutions like SecureAuth OTP which ...
1
vote
2answers
1k views

Is there a way to create time based OTP with public/private key

I have a situation where I need time based OTP. But most of the examples and cases I have seen, uses same key to create and check otp. But I need something different. I want to create OTP using a ...
3
votes
1answer
418 views

TOTP / HOTP - Offline 1 hour password generator

I need to generate and valid a password / token for an hour. Client -> generate password (valid for one hour) Server -> valid it within an hour. //System needs to work offline (TOTP) TOTP is ...
1
vote
4answers
357 views

Implementation flow of MFA with TOTP

For a frontend, i would like to implement MFA (with TOTP). I may be searching for the wrong keywords but i couldn't find the proper way to implement securely this solution. I was searching for a ...
1
vote
0answers
192 views

Is the password for Amazon's Kindle for PC stored on the computer's hard drive?

When first using Amazon's "Kindle for PC," it asks you for a password. Subsequent times using "Kindle for PC," it doesn't ask you for your password. Is that password stored on the computer's hard ...
6
votes
3answers
2k views

Is it secure to store a two factor authentication seed in a password manager?

I wonder whether it is really secure to store the Two Factor Authentication seed code (e.g. the secret key for TOTP) within a password manager together with the user and password for the service. If ...
17
votes
4answers
4k views

One Time Password Algorithm for Humans

Is there a one time password generation algorithm (based on predefined secret and a changing value/time/counter/etc) that is simple enough that it can be processed by an average human but safe enough ...
3
votes
1answer
981 views

OTP vs. U2F for online banking and email (vs. store key on USB)

Which one among OATH HOTP, OATH TOTP on one side (say in the form of a credit card-sized token) and U2F (say in the form of a USB key) on the other side you think is more secure for purposes like ...
1
vote
1answer
135 views

Resetting password everytime you login

It is a good idea in terms of security wise, to reset your password everytime you login and just fill your password with a bunch of random symbols,letters and words that you don't memorise? Since ...
10
votes
3answers
2k views

Why are one time password reset links safer than one time passwords?

Recently I applied for a job at a company creating security-critical solutions for military, aerospace, ... After registering at their webpage, I received an email with my username and a ...