diff --git a/web/data/versions.json b/web/data/versions.json
index e90c41de54e8bfc1054871c66aab3ad73a25d5cd..56c1b01e75dc81a871da74ebe3742f232b5c2998 100644
--- a/web/data/versions.json
+++ b/web/data/versions.json
@@ -39,8 +39,8 @@
       "https://github.com/joergbuchwald/ogs6py/archive/0f9e738e2ee469c8bde4204b2151238973417694.zip",
       "https://github.com/joergbuchwald/VTUinterface/archive/refs/heads/master.zip",
       "https://github.com/bilke/nb2hugo/archive/e27dc02df2be1ce19e4a6f52d197c2e2a6ca520c.zip",
-      "ipykernel",
-      "nbconvert"
+      "ipykernel==6.7.0",
+      "nbconvert==6.4.0"
     ]
   }
 }