diff --git a/files/lib/data/conversation/message/ConversationMessage.class.php b/files/lib/data/conversation/message/ConversationMessage.class.php
index bfb720ea..f75683c9 100644
--- a/files/lib/data/conversation/message/ConversationMessage.class.php
+++ b/files/lib/data/conversation/message/ConversationMessage.class.php
@@ -225,4 +225,26 @@ public function getUserProfile(): UserProfile
     {
         return $this->getCollection()->getUserProfile($this);
     }
+
+    /**
+     * Checks if the current user can read this particular message.
+     */
+    public function canRead(): bool
+    {
+        $conversation = $this->getConversation();
+        if ($conversation === null) {
+            return false;
+        }
+
+        $participant = $conversation->getParticipant();
+        if ($participant === null) {
+            return false;
+        }
+
+        if ($participant->hasJoinedAfter($this->time) || $participant->hasLeftBefore($this->time)) {
+            return false;
+        }
+
+        return true;
+    }
 }
diff --git a/files/lib/data/conversation/participant/ConversationParticipant.class.php b/files/lib/data/conversation/participant/ConversationParticipant.class.php
index b531f67a..ec288e2d 100644
--- a/files/lib/data/conversation/participant/ConversationParticipant.class.php
+++ b/files/lib/data/conversation/participant/ConversationParticipant.class.php
@@ -37,6 +37,32 @@ class ConversationParticipant extends DatabaseObject
      */
     protected static $databaseTableIndexName = 'conversationParticipantID';
 
+    /**
+     * Returns true if the user has joined the conversation after the provided
+     * timestamp.
+     */
+    public function hasJoinedAfter(int $timestamp): bool
+    {
+        if ($this->joinedAt === 0) {
+            return false;
+        }
+
+        return $this->joinedAt > $timestamp;
+    }
+
+    /**
+     * Returns true if the user has left the conversation before the provided
+     * timestamp.
+     */
+    public function hasLeftBefore(int $timestamp): bool
+    {
+        if ($this->leftAt === 0) {
+            return false;
+        }
+
+        return $this->leftAt < $timestamp;
+    }
+
     public static function getParticipant(int $conversationID, int $userID): ?static
     {
         $sql = "SELECT * FROM wcf1_conversation_to_user WHERE conversationID = ? AND userID = ?";
diff --git a/files/lib/system/message/quote/ConversationMessageQuoteHandler.class.php b/files/lib/system/message/quote/ConversationMessageQuoteHandler.class.php
new file mode 100644
index 00000000..718af831
--- /dev/null
+++ b/files/lib/system/message/quote/ConversationMessageQuoteHandler.class.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace wcf\system\message\quote;
+
+use wcf\data\conversation\message\ConversationMessage;
+use wcf\data\IMessage;
+
+/**
+ * IMessageQuoteHandler implementation for conversation messages.
+ *
+ * @author      Alexander Ebert
+ * @copyright   2001-2025 WoltLab GmbH
+ * @license     WoltLab License <http://www.woltlab.com/license-agreement.html>
+ */
+final class ConversationMessageQuoteHandler extends AbstractMessageQuoteHandler
+{
+    #[\Override]
+    public function getMessage(int $objectID): ?IMessage
+    {
+        $message = new ConversationMessage($objectID);
+        if (!$message->messageID) {
+            return null;
+        }
+
+        if (!$message->canRead()) {
+            return null;
+        }
+
+        if ($message->hasEmbeddedObjects) {
+            $message->getCollection()->loadEmbeddedObjects();
+        }
+
+        return $message;
+    }
+}
diff --git a/objectType.xml b/objectType.xml
index 60e28252..23b9ea24 100644
--- a/objectType.xml
+++ b/objectType.xml
@@ -32,6 +32,7 @@
 		<type>
 			<name>com.woltlab.wcf.conversation.message</name>
 			<definitionname>com.woltlab.wcf.message.quote</definitionname>
+			<classname>wcf\system\message\quote\ConversationMessageQuoteHandler</classname>
 		</type>
 		<type>
 			<name>com.woltlab.wcf.conversation.message</name>
diff --git a/templates/conversation.tpl b/templates/conversation.tpl
index 490b3e11..e18b8334 100644
--- a/templates/conversation.tpl
+++ b/templates/conversation.tpl
@@ -84,7 +84,7 @@
 	], ({ UiConversationMessageInlineEditor }, { registerContainer }, { getParticipantList }) => {
 		new UiConversationMessageInlineEditor({$conversation->conversationID});
 
-		registerContainer(".message", ".messageBody", "wcf\\data\\conversation\\message\\ConversationMessage", "com.woltlab.wcf.conversation.message");
+		registerContainer(".message", ".messageBody", "com.woltlab.wcf.conversation.message");
 
 		const contextMenu = document.getElementById('{unsafe:$interactionContextMenu->getContainerID()|encodeJS}')
 		console.log(contextMenu);