diff --git a/cli/cmd/dir.go b/cli/cmd/dir.go
index a7404a4..7cbdd5d 100644
--- a/cli/cmd/dir.go
+++ b/cli/cmd/dir.go
@@ -64,38 +64,40 @@ func parseDirOptions() (*libgobuster.Options, *gobusterdir.OptionsDir, error) {
 	if err != nil {
 		return nil, nil, fmt.Errorf("invalid value for extensions: %w", err)
 	}
-
-	if plugin.Extensions != "" {
-		ret, err := helper.ParseExtensions(plugin.Extensions)
-		if err != nil {
-			return nil, nil, fmt.Errorf("invalid value for extensions: %w", err)
-		}
-		plugin.ExtensionsParsed = ret
+	ret, err := helper.ParseExtensions(plugin.Extensions)
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid value for extensions: %w", err)
 	}
+	plugin.ExtensionsParsed = ret
 
+	// parse normal status codes
+	plugin.StatusCodes, err = cmdDir.Flags().GetString("status-codes")
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid value for status-codes: %w", err)
+	}
+	ret2, err := helper.ParseCommaSeparatedInt(plugin.StatusCodes)
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid value for status-codes: %w", err)
+	}
+	plugin.StatusCodesParsed = ret2
+
+	// blacklist will override the normal status codes
 	plugin.StatusCodesBlacklist, err = cmdDir.Flags().GetString("status-codes-blacklist")
 	if err != nil {
 		return nil, nil, fmt.Errorf("invalid value for status-codes-blacklist: %w", err)
 	}
+	ret3, err := helper.ParseCommaSeparatedInt(plugin.StatusCodesBlacklist)
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid value for status-codes-blacklist: %w", err)
+	}
+	plugin.StatusCodesBlacklistParsed = ret3
 
-	// blacklist will override the normal status codes
-	if plugin.StatusCodesBlacklist != "" {
-		ret, err := helper.ParseCommaSeparatedInt(plugin.StatusCodesBlacklist)
-		if err != nil {
-			return nil, nil, fmt.Errorf("invalid value for status-codes-blacklist: %w", err)
-		}
-		plugin.StatusCodesBlacklistParsed = ret
-	} else {
-		// parse normal status codes
-		plugin.StatusCodes, err = cmdDir.Flags().GetString("status-codes")
-		if err != nil {
-			return nil, nil, fmt.Errorf("invalid value for status-codes: %w", err)
-		}
-		ret, err := helper.ParseCommaSeparatedInt(plugin.StatusCodes)
-		if err != nil {
-			return nil, nil, fmt.Errorf("invalid value for status-codes: %w", err)
-		}
-		plugin.StatusCodesParsed = ret
+	if plugin.StatusCodes != "" && plugin.StatusCodesBlacklist != "" {
+		return nil, nil, fmt.Errorf("status-codes and status-codes-blacklist are both set, pleaes set only one")
+	}
+
+	if plugin.StatusCodes == "" && plugin.StatusCodesBlacklist == "" {
+		return nil, nil, fmt.Errorf("status-codes and status-codes-blacklist are both not set, pleaes set one")
 	}
 
 	plugin.UseSlash, err = cmdDir.Flags().GetBool("add-slash")
diff --git a/cli/cmd/fuzz.go b/cli/cmd/fuzz.go
index 37ce185..3b26c2c 100644
--- a/cli/cmd/fuzz.go
+++ b/cli/cmd/fuzz.go
@@ -60,19 +60,16 @@ func parseFuzzOptions() (*libgobuster.Options, *gobusterfuzz.OptionsFuzz, error)
 	plugin.Headers = httpOpts.Headers
 	plugin.Method = httpOpts.Method
 
+	// blacklist will override the normal status codes
 	plugin.ExcludedStatusCodes, err = cmdFuzz.Flags().GetString("excludestatuscodes")
 	if err != nil {
 		return nil, nil, fmt.Errorf("invalid value for excludestatuscodes: %w", err)
 	}
-
-	// blacklist will override the normal status codes
-	if plugin.ExcludedStatusCodes != "" {
-		ret, err := helper.ParseCommaSeparatedInt(plugin.ExcludedStatusCodes)
-		if err != nil {
-			return nil, nil, fmt.Errorf("invalid value for excludestatuscodes: %w", err)
-		}
-		plugin.ExcludedStatusCodesParsed = ret
+	ret, err := helper.ParseCommaSeparatedInt(plugin.ExcludedStatusCodes)
+	if err != nil {
+		return nil, nil, fmt.Errorf("invalid value for excludestatuscodes: %w", err)
 	}
+	plugin.ExcludedStatusCodesParsed = ret
 
 	plugin.ExcludeLength, err = cmdFuzz.Flags().GetIntSlice("exclude-length")
 	if err != nil {
diff --git a/go.mod b/go.mod
index 64f1df0..346d127 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module github.com/OJ/gobuster/v3
 require (
 	github.com/google/uuid v1.2.0
 	github.com/spf13/cobra v1.1.3
-	golang.org/x/sys v0.0.0-20210223212115-eede4237b368 // indirect
+	golang.org/x/sys v0.0.0-20210301091718-77cc2087c03b // indirect
 	golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d
 )
 
diff --git a/go.sum b/go.sum
index 8c86b3c..c6cf1aa 100644
--- a/go.sum
+++ b/go.sum
@@ -228,8 +228,8 @@ golang.org/x/sys v0.0.0-20190507160741-ecd444e8653b/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190606165138-5da285871e9c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190624142023-c5567b49c5d0/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210223212115-eede4237b368 h1:fDE3p0qf2V1co1vfj3/o87Ps8Hq6QTGNxJ5Xe7xSp80=
-golang.org/x/sys v0.0.0-20210223212115-eede4237b368/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210301091718-77cc2087c03b h1:kHlr0tATeLRMEiZJu5CknOw/E8V6h69sXXQFGoPtjcc=
+golang.org/x/sys v0.0.0-20210301091718-77cc2087c03b/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d h1:SZxvLBoTP5yHO3Frd4z4vrF+DBX9vMVanchswa69toE=
 golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
diff --git a/helper/helper.go b/helper/helper.go
index 40f1caf..1efac08 100644
--- a/helper/helper.go
+++ b/helper/helper.go
@@ -11,7 +11,7 @@ import (
 // ParseExtensions parses the extensions provided as a comma separated list
 func ParseExtensions(extensions string) (libgobuster.StringSet, error) {
 	if extensions == "" {
-		return libgobuster.StringSet{}, fmt.Errorf("invalid extension string provided")
+		return libgobuster.StringSet{}, nil
 	}
 
 	ret := libgobuster.NewStringSet()
@@ -26,7 +26,7 @@ func ParseExtensions(extensions string) (libgobuster.StringSet, error) {
 // ParseCommaSeparatedInt parses the status codes provided as a comma separated list
 func ParseCommaSeparatedInt(inputString string) (libgobuster.IntSet, error) {
 	if inputString == "" {
-		return libgobuster.IntSet{}, fmt.Errorf("invalid string provided")
+		return libgobuster.IntSet{}, nil
 	}
 
 	ret := libgobuster.NewIntSet()