diff --git a/AK/URLParser.cpp b/AK/URLParser.cpp
index bbd80f04bc4..89e656d16eb 100644
--- a/AK/URLParser.cpp
+++ b/AK/URLParser.cpp
@@ -120,18 +120,22 @@ static Optional<ParsedIPv4Number> parse_ipv4_number(StringView input)
     }
 
     // 8. Let output be the mathematical integer value that is represented by input in radix-R notation, using ASCII hex digits for digits with values 0 through 15.
-    u32 output;
+    Optional<u32> maybe_output;
     if (radix == 8)
-        output = StringUtils::convert_to_uint_from_octal(input).release_value();
+        maybe_output = StringUtils::convert_to_uint_from_octal(input);
     else if (radix == 10)
-        output = input.to_uint().release_value();
+        maybe_output = input.to_uint();
     else if (radix == 16)
-        output = StringUtils::convert_to_uint_from_hex(input).release_value();
+        maybe_output = StringUtils::convert_to_uint_from_hex(input);
     else
         VERIFY_NOT_REACHED();
 
+    // NOTE: Parsing may have failed due to overflow.
+    if (!maybe_output.has_value())
+        return {};
+
     // 9. Return (output, validationError).
-    return ParsedIPv4Number { output, validation_error };
+    return ParsedIPv4Number { maybe_output.value(), validation_error };
 }
 
 // https://url.spec.whatwg.org/#concept-ipv4-parser
diff --git a/Tests/AK/TestURL.cpp b/Tests/AK/TestURL.cpp
index 7ea6be99615..04edd8a0a00 100644
--- a/Tests/AK/TestURL.cpp
+++ b/Tests/AK/TestURL.cpp
@@ -535,4 +535,10 @@ TEST_CASE(ipv4_address)
         EXPECT(url.is_valid());
         EXPECT_EQ(MUST(url.serialized_host()), "52.251.94.56"sv);
     }
+
+    {
+        constexpr auto ipv4_url = "http://9111111111"sv;
+        URL url(ipv4_url);
+        EXPECT(!url.is_valid());
+    }
 }