diff --git a/bin/tests/system/nsec3-answer/tests_nsec3.py b/bin/tests/system/nsec3-answer/tests_nsec3.py
index 12ccd16f75..2ee8a4fa49 100755
--- a/bin/tests/system/nsec3-answer/tests_nsec3.py
+++ b/bin/tests/system/nsec3-answer/tests_nsec3.py
@@ -273,7 +273,7 @@ def check_wildcard_synthesis(qname: dns.name.Name, nsec3check: "NSEC3Checker") -
     nsec3check.check_extraneous_rrs()
 
 
-@dataclass(kw_only=True, frozen=True)
+@dataclass(frozen=True)
 class NSEC3Params:
     """Common values from a single DNS response"""