owncloud.com: Parameter pollution in social sharing buttons

How it was found

Hello Owncloud ! For Example , We Have a Link :

https://owncloud.com/blog-you-can-soon-be-fined/

And We Change It To :-

https://owncloud.com/blog-you-can-soon-be-fined/?u=https://vk.com&text=another_site:https://hackerone.com/gorang_joshi

So When You Share It , While Using Your Sharing Buttons Present On Your Page , The Source Code Will Change : Facebook : https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fowncloud.com%2Fblog-you-can-soon-be-fined%2F%3Fu%3Dhttps%3A%2F%2Fvk.com&text=another_site%3Ahttps%3A%2F%2Fhackerone.com%2Fgorang_joshi

twitter :https://twitter.com/intent/tweet?text=another_site%3Ahttps%3A%2F%2Fhackerone.com%2Fgorang_joshi&url=https%3A%2F%2Fowncloud.com%2Fblog-you-can-soon-be-fined%2F%3Fu%3Dhttps%3A%2F%2Fvk.com&original_referer=

Thanks , The Same Report Was Reported By My Friend To Hackerone , You Can Check This Here :

https://hackerone.com/reports/105953

Thanks , Hope You'll Response Likewise :)