diff --git a/setup/webmail.sh b/setup/webmail.sh
index 548cdfb2..5ea749a3 100644
--- a/setup/webmail.sh
+++ b/setup/webmail.sh
@@ -36,8 +36,8 @@ apt_install \
 #   https://github.com/mstilkerich/rcmcarddav/releases
 # The easiest way to get the package hashes is to run this script and get the hash from
 # the error message.
-VERSION=1.6.19
-HASH=d30d11f91857b1962879e06a19ef217dceeb506c
+VERSION=1.6.20
+HASH=15c70410af3071219aae209ba89e2ff1dacb1ab5
 PERSISTENT_LOGIN_VERSION=bde7b6840c7d91de627ea14e81cf4133cbb3c07a # version 5.3
 HTML5_NOTIFIER_VERSION=68d9ca194212e15b3c7225eb6085dbcf02fd13d7 # version 0.6.4+
 CARDDAV_VERSION=4.4.3