diff --git a/servconf.c b/servconf.c
index 1e88905..f20504b 100644
--- a/servconf.c
+++ b/servconf.c
@@ -1562,7 +1562,7 @@ process_server_config_line(ServerOptions *options, char *line,
 		break;
 
 	case sForceCommand:
-		if (cp == NULL)
+		if (cp == NULL || *cp == '\0')
 			fatal("%.200s line %d: Missing argument.", filename,
 			    linenum);
 		len = strspn(cp, WHITESPACE);
@@ -1607,7 +1607,7 @@ process_server_config_line(ServerOptions *options, char *line,
 		break;
 
 	case sVersionAddendum:
-		if (cp == NULL)
+		if (cp == NULL || *cp == '\0')
 			fatal("%.200s line %d: Missing argument.", filename,
 			    linenum);
 		len = strspn(cp, WHITESPACE);
@@ -1642,6 +1642,8 @@ process_server_config_line(ServerOptions *options, char *line,
 		break;
 
 	case sAuthenticationMethods:
+		if (cp == NULL || *cp == '\0')
+			fatal("%.200s line %d: Missing argument.", filename, linenum);
 		if (*activep && options->num_auth_methods == 0) {
 			while ((arg = strdelim(&cp)) && *arg != '\0') {
 				if (options->num_auth_methods >=