diff --git a/lib/promrelabel/config.go b/lib/promrelabel/config.go
index f0df2073be..3555cb55b4 100644
--- a/lib/promrelabel/config.go
+++ b/lib/promrelabel/config.go
@@ -28,7 +28,7 @@ func LoadRelabelConfigs(path string) ([]ParsedRelabelConfig, error) {
 		return nil, fmt.Errorf("cannot read `relabel_configs` from %q: %s", path, err)
 	}
 	var rcs []RelabelConfig
-	if err := yaml.Unmarshal(data, &rcs); err != nil {
+	if err := yaml.UnmarshalStrict(data, &rcs); err != nil {
 		return nil, fmt.Errorf("cannot unmarshal `relabel_configs` from %q: %s", path, err)
 	}
 	return ParseRelabelConfigs(nil, rcs)
diff --git a/lib/promscrape/config.go b/lib/promscrape/config.go
index 77249cb7aa..36a28c8967 100644
--- a/lib/promscrape/config.go
+++ b/lib/promscrape/config.go
@@ -102,7 +102,7 @@ func loadStaticConfigs(path string) ([]StaticConfig, error) {
 		return nil, fmt.Errorf("cannot read `static_configs` from %q: %s", path, err)
 	}
 	var stcs []StaticConfig
-	if err := yaml.Unmarshal(data, &stcs); err != nil {
+	if err := yaml.UnmarshalStrict(data, &stcs); err != nil {
 		return nil, fmt.Errorf("cannot unmarshal `static_configs` from %q: %s", path, err)
 	}
 	return stcs, nil