diff --git a/tests/compat.sh b/tests/compat.sh
index 560af59..ee2d460 100755
--- a/tests/compat.sh
+++ b/tests/compat.sh
@@ -930,6 +930,20 @@
     G_CLIENT_ARGS="-p $PORT --debug 3 $G_MODE"
     G_CLIENT_PRIO="NONE:$G_PRIO_MODE:+COMP-NULL:+CURVE-ALL:+SIGN-ALL"
 
+    # Newer versions of OpenSSL have a syntax to enable all "ciphers", even
+    # low-security ones. This covers not just cipher suites but also protocol
+    # versions. It is necessary, for example, to use (D)TLS 1.0/1.1 on
+    # OpenSSL 1.1.1f from Ubuntu 20.04. The syntax was only introduced in
+    # OpenSSL 1.1.0 (21e0c1d23afff48601eb93135defddae51f7e2e3) and I can't find
+    # a way to discover it from -help, so check the openssl version.
+    case $($OPENSSL_CMD version) in
+        "OpenSSL 0"*|"OpenSSL 1.0"*) :;;
+        *)
+            O_CLIENT_ARGS="$O_CLIENT_ARGS -cipher ALL@SECLEVEL=0"
+            O_SERVER_ARGS="$O_SERVER_ARGS -cipher ALL@SECLEVEL=0"
+            ;;
+    esac
+
     if [ "X$VERIFY" = "XYES" ];
     then
         M_SERVER_ARGS="$M_SERVER_ARGS ca_file=data_files/test-ca_cat12.crt auth_mode=required"