CM User Submitted Posts - Uploading Images
The user Submitted Posts plugin can allow users submitting posts via the form to include images in their posts.
Adding Media to the content of the Post via text editor
Users will be able to add images to the post using HTML if you have enabled the text editor. To enable this navigate to Admin Dashboard → CM User Submitted Posts → Form Settings tab. Find there the option Text editor and enable it, then click Save Changes at the bottom of the page.
Now a text editor option will appear allowing users to post using HTML. With the <img> element they can include images.
Adding images using the visual editor
It is also possible to enable an Add Media button to the form so that users can include images using the visual editor.
On the same tab Form Settings find the option Media in editor and turn it on, then click Save Changes.
Now an Add Media button appears on the Form that users can use to include images by browsing their files.