Change attached img anchor link to post link

You may try the filter wp_get_attachment_link

// definition: apply_filters( 'wp_get_attachment_link', "<a href="" . esc_url( $url ) . "">$link_text</a>", $id, $size, $permalink, $icon, $text, $attr );

// this filter provide a max. of 7 arguments, I use 2 in the example
add_filter( 'wp_get_attachment_link', 'q363693_update_attachment_link', 10, 2 );
function q363693_update_attachment_link( $url, $id ) {
   // some codes
   $new_link = "<a href="" . get_permalink( $id ) . "">your own text or anything you need or add more arguments to use the original text...</a>";

   return $new_link;
}