diff --git a/webmails/Dockerfile b/webmails/Dockerfile
index 31774393..d233a1a8 100644
--- a/webmails/Dockerfile
+++ b/webmails/Dockerfile
@@ -29,7 +29,7 @@ RUN set -euxo pipefail \
   ; mkdir -p /run/nginx /conf
 
 # roundcube
-ENV ROUNDCUBE_URL https://github.com/roundcube/roundcubemail/releases/download/1.6.5/roundcubemail-1.6.5-complete.tar.gz
+ENV ROUNDCUBE_URL https://github.com/roundcube/roundcubemail/releases/download/1.6.6/roundcubemail-1.6.6-complete.tar.gz
 ENV CARDDAV_URL https://github.com/mstilkerich/rcmcarddav/releases/download/v5.1.0/carddav-v5.1.0.tar.gz
 
 RUN set -euxo pipefail \