diff --git a/make.sh b/make.sh
index 5ffac4517d8e81e62ed2009626151e674318f34e..63428e40f685e0b2c86a48179a9a6cdfc48d18fd 100755
--- a/make.sh
+++ b/make.sh
@@ -11,7 +11,7 @@ deb-src http://ftp.zcu.cz/pub/linux/debian-security bullseye-security main contr
 EOSOURCES
 
 apt update -qqq
-apt install git build-essential heimdal-dev --no-install-recommends -qqq -y
+apt install git ca-certificates build-essential heimdal-dev --no-install-recommends -qqq -y
 
 git clone https://github.com/cesnet/krb525