diff --git a/crates/oxc_linter/src/rules/unicorn/explicit_length_check.rs b/crates/oxc_linter/src/rules/unicorn/explicit_length_check.rs
index d7edc151e55de..442e17503c905 100644
--- a/crates/oxc_linter/src/rules/unicorn/explicit_length_check.rs
+++ b/crates/oxc_linter/src/rules/unicorn/explicit_length_check.rs
@@ -46,7 +46,7 @@ enum NonZero {
 }
 
 #[derive(Debug, Default, Clone, JsonSchema, Deserialize)]
-#[serde(rename_all = "kebab-case", default)]
+#[serde(rename_all = "kebab-case", default, deny_unknown_fields)]
 pub struct ExplicitLengthCheck {
     /// Configuration option to specify how non-zero length checks should be enforced.
     ///
@@ -266,9 +266,7 @@ impl ExplicitLengthCheck {
 
 impl Rule for ExplicitLengthCheck {
     fn from_configuration(value: serde_json::Value) -> Result<Self, serde_json::error::Error> {
-        Ok(serde_json::from_value::<DefaultRuleConfig<Self>>(value)
-            .unwrap_or_default()
-            .into_inner())
+        serde_json::from_value::<DefaultRuleConfig<Self>>(value).map(DefaultRuleConfig::into_inner)
     }
 
     fn run<'a>(&self, node: &AstNode<'a>, ctx: &LintContext<'a>) {