diff --git a/index.yaml b/index.yaml
index 16f348c..ccfbf9d 100644
--- a/index.yaml
+++ b/index.yaml
@@ -210,6 +210,7 @@ sources:
     min-version: 4.1.0
     homepage: https://raw-data.gitlab.io/post/malsilo_2.1/
     checksum: true
+    obsolete: unmaintained
 
   stamus/lateral:
     summary: Lateral movement rules