diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index ea513b2f3..e5cee539c 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -4656,6 +4656,9 @@ static char **crtlist_dup_filters(char **args, int fcount)
 	char **dst;
 	int i;
 
+	if (fcount == 0)
+		return NULL;
+
 	dst = calloc(fcount + 1, sizeof(*dst));
 	if (!dst)
 		return NULL;