Coinbase: ByPassing the email Validation Email on Sign up process in mobile apps

Hi, According to the design When the new user sign up using mobile appsandroid,ios.It will ask for the confirmation of the email.It will send a confirmation mail to mail id and a screen will also appear in the mobile app. The user needs to open the email in the device then the screen will Off and...

Coinbase: iframes considered harmful

The Coinbase API offers an iframe payment option. iframes are attractive because they allow Coinbase's customers to give the illusion that the Bitcoin transaction is embedded entirely within the customer's website. But customers can and do refer to that iframe on insecure connections. Hijacking a...

Coinbase: Sandboxed iframes don't show confirmation screen

Just like I anticipated in 2013 http://homakov.blogspot.com/2013/04/html5-sandbox-bad-idea.html sandbox was a bad idea. As a payment gateway you do your best to seamlessly integrate with your customers and allow showing checkout in iframes. To prevent basic clickjacking you have data-confirm...

Coinbase: open authentication bug

Hi, If developer registers one of the three url's with out http protocol ex:example.com in oauth registration then he would be redirected to www.coinbase.comexample.com.This makes the user to redirect to another site than the real application.Attacker could take advantage of this and steal the...

Coinbase: New Device Confirmation, token is valid until not used.

New Device Confirmation token sends to the logged in user from unconfirmed device. Now If Click on Account or Settings or Profile email of new token will send to that person and same if user click multiple times, more and more confirmation emails user received. On each reload each confirmation...

Coinbase: New Device confirmation tokens are not properly validated.

Hi, team I noticed that the new device confirmation code sent by your server is not validated . POC: 1 Login to a new computer and ask for confirmation code two times. Say around at 12.00 PM and at 12.01 PM 2 Now verify the device with the confirmation token which arrived at 12.01 PM and after...

Coinbase: Credit Card Validation Issue

Hi Coinbase, I'm not sure if this counts as a bug, but it definitely counts as a vulerability. The issue is in your credit card verification for instant purchases. The system does not or rarely check the validity of a credit card after it is added. This allows me to make instant buy purchases,...

Coinbase: Invoice Details activate JS that filled in

Hello security team, I found XSS on pending invocation details. Tested on Firefox. Scenario: 1. Go to https://coinbase.com/merchanttools?linktype=emailinvoice 2. Fill in valid email. 3. Subject; Payment request from " 4. Total Bitcoin 1 and for order put a " 5. Description and Customer ID as a " ...

Coinbase: 2FA settings allowed to be changed with no delay/freeze on funds

With the nature of bitcoin's instant transactions and the increase level of phishing/malware attempts on users, many bitcoin related businesses have freeze/delays on funds once a user changes their 2FA settings. That design keeps the 2FA from being defeated instantly if the user's email account h...

Coinbase: Leaking CSRF token over HTTP resulting in CSRF protection bypass

Start a proxy tool like Burp. 2. Authenticate to the Coinbase application. 3. Navigate to the URL https://coinbase.com/docs/api/overview 4. Under Developer Updates, enter your email address and click "Subscribe". 5. Notice that this request is sent over HTTP with the CSRF token in the body of...

Coinbase: CSRF in function "Set as primary" on accounts page

I would like to report this CSRF vulnerability in coinbase on function "set as primary" for a account in accounts page. Steps: 1 Login to your coinbase account which atleast has two accounts 2 Go to "accounts" page and out of the two accounts click "set as primary" link for one of the accounts...

Coinbase: Bypassing 2FA for BTC transfers

Under advanced settings, users have the ability to protect their wallet by requiring two-factor confirmation when sending bitcoins. Personally, I have configured my account with the most secure option, which requires two factor confirmation when sending any amount of bitcoins. However, a flaw...

Malicious Chrome Extension Hijacks CryptoCurrencies and Wallets

Although the number of malicious browser extensions has significantly increased in the past years, but recently a new extension of the Google Chrome is allegedly targeting Cryptocurrency users that is capable of stealing Bitcoins and other crypto coins silently. The malicious Chrome browser...

Coinbase: Multiple Issues related to registering applications

On the page https://coinbase.com/oauth/applications, an authenticated coinbase user can create an application and successfully submit it to the app gallery. After submitting, the app is pending review to be approved. However, while the app is in review, the coinbase user can send a URL something...

Coinbase: Coinbase Android Application - Bitcoin Wallet Leaks OAuth Response Code

Hi, There's a simple bug here, the Coinbase Android App. "BitCoin Wallet" leaks the OAuth Response Code which can be obtained using adb logcat -s Coinbase command line for testing, and any Android application on the same phone can read the response code for the user by reading the logs. As of now...

Coinbase: IFRAME loaded from External Domains

Hello coinbase, Iam saikiran.Iam a security researcher.while i was going through your site i found that your website loads an iframe from an external website which might not be trustworthy.IFRAME has been loaded in the page 'https://coinbase.com/charts' from 'www.statsmix.com' which is an externa...

Coinbase: Cookie missing the HttpOnly flag

Hello coinbase, Iam saikiran.Iam a security researcher.while i was going through your site i found that your website does not have HTTPOnly flag for the cookies.it is not a vulnerability but it is a new improvement and improves the security of your site. If your not aware of HTTPOnly flag here is...

Coinbase: User Enumeration, Information Disclosure and Lack of Rate Limitation on API

NOTE: I am making this email as I think the response from Coinbase originally, via my emails to them was not correct. They had not acknowledged that this flaw allowed for user enumeration and hence I am posting the report again - in hope of a proper and well evaluated response. The key security...

Coinbase: Improper Validation of the Referrer header leading to Open URL Redirection

Using a proxy tool such as Burp, set the Target as https://coinbase.com. Then, send the following request: GET /cdn-cgi/l/chkjschl HTTP/1.1 Host: coinbase.com Referer: http://attacker.com Content-Length: 2 Notice the attacker's domain in the Referrer header. This value is not being validated on t...

Coinbase: Information Disclosure That shows the webroot of CoinBase Server

Hello, While I was testing The upload method on https://coinbase.com/merchantsettings , I have found that if you try to upload a php file or any other file html in this shape test.php.jpg , an Information Disclosure will happen showing the webroot of the server. I have provide a screenshot to...