Is There A WordPress Hook for Accessing Attachments for A Particular Page?

Here’s one way, out of many, where we use the the_content filter and loop through the get_attached_media( $type ) to construct the list of attached media. We can e.g. use $type="image" for images or $type = null for all mime types.

add_filter( 'the_content', function( $content )
{
    // Nothing to do - target single posts assigned to the 'report' category 
    if( ! in_the_loop() || ! is_single() || ! has_category( 'report' ) )      
        return $content;

    // Reduce attached media items into a string
    $li = array_reduce(                           
        get_attached_media( $type = null ),       // Fetch the attached media (all == null)
        function( $li, $item )                    // Callback for each media item
        {
            $li .= sprintf(                       // Construct and append each list item
                '<li>%s</li>',
                wp_get_attachment_link( $item->ID, false ) 
            );
            return $li;
        },
        ''                                         // Initial value of $li
    );

    // Append to the content
    if( $li )
        $content .= sprintf( '<ul class="attached-media">%s</ul>', $li);

    return $content;

}, 999 );                                           // Some late priority

Here we display the attached media list only for single posts, assigned to the report category.