Put CSP everywhere (#7810)

* Puts CSP everywhere in `p/api`
   * including the HTML query page ❗
   * Also in `p/ext.php`
* Puts `X-Content-Type-Options: nosniff` everywhere
* Fixes custom icon configuration not showing `blob:` icon in statsController (idle feeds)
   * Also removes `style-src 'unsafe-inline'` since it doesn't seem to be needed
* Improves CSP of `p/f.php`

* Add `sandbox` directive

1 files changed, 2 insertions, 0 deletions

diff --git a/p/ext.php b/p/ext.php
index f470b7210..5fdd3df6c 100644
--- a/p/ext.php
+++ b/p/ext.php
@@ -94,6 +94,8 @@ if (!is_valid_path($absolute_filename)) {
 $content_type = FreshRSS_extension_Controller::MIME_TYPES[$file_type];
 header("Content-Type: {$content_type}");
 header("Content-Disposition: inline; filename='{$file_name}'");
+header("Content-Security-Policy: default-src 'self'; frame-ancestors 'none'");
+header('X-Content-Type-Options: nosniff');
 header('Referrer-Policy: same-origin');
 
 $mtime = @filemtime($absolute_filename);