Categories
Bug Bounty

How I earned 5040$ from Twitter by showing a way to Harvest other users IP address

Hi guys,
This is one of my old finding adding to my blog. Recently I disclosed a POC on How I was able to get all vine user’s sensitive Information including Phone no/IP Address/Emails and Many more that was reported to Twitter and they patched it and rewarded me 7560$. Those who missed it you can get the Orginal Report Here.

Today I am going to disclose another Information Disclosure vulnerability that was reported by me to the Twitter Security team in their Bug Bounty Program in Hackerone and they Rewarded me with an amount of 5040$ for this report.

When I testing vine API Endpoints I noticed an Endpoint that uses in the Vine Repost mechanism have a Parameter Named "ipAddress" with some plain Number value Like: 2130706433. We all know Ip Addresses look like: 127.0.0.1, But the value of the "ipAddress" looks invalid. Then when I tried to search about it on google I came to know that the value is valid. Actually, it was Converted to IP Address to Long/Decimal format. So I used an Online Converter tool and was able to get the real Ip.

Vulnerable Endpoint: https://vine.co/api/timelines/users/<POST_ID>

Reproduce
  • To reproduce this issue victim User have to repost any vine in his timeline and a lot of vine users reposted many Vine post in their timeline.
  • So Copy a Reposted Vine POST_ID and place it in the Endpoint and visit it. Example: https://vine.co/api/timelines/users/1293308695089926144
  • Now when I visited the link I got a response like below (The sensitive contents were removed by the twitter security team)
    “repost”: { “username”: “██████”, “verified”: 0, “vanityUrls”: [], “created”: “█████”, “repostId”: ████████, “avatarUrl”: “██████”, “userId”: ████, “user”: { “username”: “█████████”, “verified”: 0, “vanityUrls”: [], “avatarUrl”: “█████████”, “userId”: ████, “private”: 0, “location”: █████████ }, “flags|platform_lo”: 1, “postId”: ███, “ipAddress”: 2130706433 , “flags|platform_hi”: 1 }
  • As you can see the ipAddress parameter value is converted now Just Use my give online tool to again convert it to valid ip address value .

I reported this issue on Jan 26th and they paid me 5040$ for reporting this on Feb 25th.

5040$ from Twitter
5040$ from Twitter

Thanks for reading. Happy Hunting.

Categories
Bug Bounty

External link warning page bypass in Zerocopter

Description:

zerocopter.com is a bug bounty platform for Ethical hackers just like Hackerone. In Zerocopter reports, users can use Markdown. Users are also allowed to give external links in reports. If a user clicks on the External link in reports then it takes the user to an external warning page like the below screenshot

Zerocopter external warning page
Zerocopter external warning page

But I was able to bypass the external warning page and redirect a user to an external link without any warning page by using Markdown

<http:1249723505> 
[Click Me](http:1249723505)

Note: In the above markdown 1249723505 this is the IP of google.com [ 74.125.68.113 ] converted into Long/Decimalusing this tool.

Reproduce
  • In a report I used [Click Me](http://google.com)</code> this markdown and the response was :
    <a href="/external_redirect?href=http%3A%2F%2Fgoogle.com" rel="noreferrer" target="_blank" title="">Click Me</a>
  • Then I used [Click Me](http://74.125.68.113) this markdown and the response was
    <a href="/external_redirect?href=http%3A%2F%2F74.125.68.113" rel="noreferrer" target="_blank" title="">Click Me</a>
  • Then I thought let’s mess up with the Protocol and changed the markdown to [Click Me](http:/google.com) and still no bypass.
  • Then I was about to use [Click Me](http:google.com) but I accidentally used [Click Me](http:google) where I forgot to give .com TLD at last in domain name in the markdown and I noticed a hope in response
    <a href="http%3Agoogle" rel="noreferrer" target="_blank" title="">Click Me</a>
  • By analyzing the behavior I got that if I use a domain name like http:google then I can bypass the external warning page. Then I remembered the IP Long/Decimal encode.
    So I used this tool to encode google.com IP to Long/Decimal** and the final markdown become [Click Me](http:1249723505) and bingo 😎

    <a href="http%3A1249723505" rel="noreferrer" target="_blank" title="">Click Me</a>
  • Now when a user will click on the link it will take the user directly to google.com instead of the external warning page. Then I reported this to Zerocopter on their responsible disclosure page and they fixed it and send me a Cool T-shirt and stickers as a reward.
Cool T-shirt and stickers as reward
Cool T-shirt and stickers as reward

Thanks for reading. Hope this will be helpful for you guys.