diff --git a/CHANGES b/CHANGES
index 263253f..3ef741b 100644
--- a/CHANGES
+++ b/CHANGES
@@ -33,6 +33,10 @@ corrections:
 	e.g. an SSL connection which the parent assumed to still be active.
 	Test: SYSTEM_SHUTDOWN
 
+	Passive (listening or receiving) addresses with empty port field bound
+	to a random port instead of terminating with error.
+	Test: TCP4_NOPORT
+
 ####################### V 1.7.2.4:
 
 corrections:
diff --git a/test.sh b/test.sh
index f127900..1fd75db 100755
--- a/test.sh
+++ b/test.sh
@@ -11859,6 +11859,50 @@ PORT=$((PORT+1))
 N=$((N+1))
 
 
+# test if TCP4-LISTEN with empty port arg terminates with error
+NAME=TCP4_NOPORT
+case "$TESTS" in
+*%$N%*|*%functions%*|*%bugs%*|*%socket%*|*%tcp%*|*%tcp4%*|*%$NAME%*)
+TEST="$NAME: test if TCP4-LISTEN with empty port arg bails out"
+# run socat with TCP4-LISTEN with empty port arg. Check if it terminates
+# immediately with return code 1
+if ! eval $NUMCOND; then :; else
+tf="$td/test$N.stdout"
+te="$td/test$N.stderr"
+t0rc="$td/test$N.rc"
+tdiff="$td/test$N.diff"
+da="test$N $(date) $RANDOM"
+CMD0="$SOCAT $opts TCP4-LISTEN: /dev/null"
+printf "test $F_n $TEST... " $N
+{ $CMD0 >/dev/null 2>"${te}0"; echo $? >"$t0rc"; } & 2>/dev/null
+pid0=$!
+sleep 1
+kill $pid0 2>/dev/null; wait
+if [ ! -f "$t0rc" ]; then
+    $PRINTF "$FAILED\n"
+    echo "$CMD0 &"
+    cat "${te}0"
+    echo "did not terminate with error"
+    numFAIL=$((numFAIL+1))
+    listFAIL="$listFAIL $N"
+elif ! echo 1 |diff - "$t0rc"; then
+    $PRINTF "$FAILED\n"
+    echo "$CMD0 &"
+    cat "${te}0"
+    echo "expected return code 1"
+    numFAIL=$((numFAIL+1))
+    listFAIL="$listFAIL $N"
+else
+    $PRINTF "$OK\n"
+    numOK=$((numOK+1))
+fi
+fi # NUMCOND
+ ;;
+esac
+PORT=$((PORT+1))
+N=$((N+1))
+
+
 ##################################################################################
 #=================================================================================
 # here come tests that might affect your systems integrity. Put normal tests
diff --git a/xio-ip.c b/xio-ip.c
index 271c8d7..bc870d2 100644
--- a/xio-ip.c
+++ b/xio-ip.c
@@ -149,6 +149,9 @@ int xiogetaddrinfo(const char *node, const char *service,
    memset(sau, 0, *socklen);
    sau->soa.sa_family = family;
 
+   if (service && service[0]=='\0') {
+      Error("empty port/service");
+   }
    /* if service is numeric we don't want to have a lookup (might take long
       with NIS), so we handle this specially */
    if (service && isdigit(service[0]&0xff)) {