mysterious clipart showing up

Good morning. I was working on adding clipart and some new templates when I noticed that there are a slew of images showing up that I do not recognize. They all have their name but above the name it shows the website from which they came.
is this something new you guys are doing? or have we been hacked?
they only way they show up is if I do a search for star or some other element
website listed under each, some with vectorportal.com, some with public-domain-photos.com, openclipart.org
but when I go to RTD to look up the image it's not there.
can you explain, please?

Those are RTD system cliparts, and the ones from vectorportal.com are there since March 2013.
As a quick check I verified that the vectorportal.com ones are within the RTD "Miscellaneous" category.
So, if your product is using that category or a group having that category included, nothing strange they're appearing.

The reason why you see them searching for "star" is because the vectorportal clips you're mentioning have "sale label starburst" as keywords, and so "star" is a match.

is it some deal you have with that website? I can't believe I haven't seen that before. I upload images regularly.
what about the other two sites?
do you allow open source websites to add images to the categories?
I just wanted to verify it wasn't something off the cuff
I appreciate your help.

All those cliparts are from free sources. The only thing they required was to be credited, and that's why you're seeing the website name.
In any case no one can add more: those are sets we uploaded ourselves back in 2013 to create some basic library for new RTD users. Those open source websites have no access to the RTD

thank you for taking the time to explain this to me.
I do appreciate your support.