diff --git a/requirements.txt b/requirements.txt
index 8d281e62d..fe8f8cf28 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,7 +10,7 @@ geoalchemy2==0.4.2
 geojson==3.0.1
 geomet==1.1.0
 kombu==5.3.2
-Markdown==3.5 # at next update, please remove replace_marker() function in toc extension 
+Markdown==3.5.1 # at next update, please remove replace_marker() function in toc extension 
 phpserialize==1.3.0 # phpserialize is only required during the migration
 psycopg2==2.9.9
 pyjwt==1.7.1