diff --git a/src/Protocol/ActivityPub/Processor.php b/src/Protocol/ActivityPub/Processor.php
index 31a37a36f1..077ba3e3fe 100644
--- a/src/Protocol/ActivityPub/Processor.php
+++ b/src/Protocol/ActivityPub/Processor.php
@@ -651,7 +651,7 @@ class Processor
 
 				$content = self::removeImplicitMentionsFromBody($content, $parent);
 			}
-			$item['content-warning'] = HTML::toBBCode($activity['summary']);
+			$item['content-warning'] = (!empty($activity['summary']) ? HTML::toBBCode($activity['summary']) : '');
 			$item['raw-body'] = $item['body'] = $content;
 		}
 
@@ -1225,7 +1225,8 @@ class Processor
 		$attributed_to = JsonLD::fetchElement($activity['as:object'], 'as:attributedTo', '@id');
 		$authorid = Contact::getIdForURL($attributed_to);
 
-		$body = HTML::toBBCode(JsonLD::fetchElement($activity['as:object'], 'as:content', '@value'));
+		$value = JsonLD::fetchElement($activity['as:object'], 'as:content', '@value');
+		$body = (!empty($value) ? HTML::toBBCode($value) : '');
 
 		$messageTags = [];
 		$tags = Receiver::processTags(JsonLD::fetchElementArray($activity['as:object'], 'as:tag') ?? []);