diff --git a/ChangeLog b/ChangeLog
index d3aee8d6d..f8234461c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2025-05-09  Bart Schaefer  <schaefer@zsh.org>
 
+	* unposted: Src/params.c: fix bad pointer found by valgrind
+
 	* 53568: Doc/Zsh/expn.yo, Doc/Zsh/params.yo, Src/params.c,
 	Test/K01nameref.ztst: fix additional problems with references
 	whose referent goes out of scope, add corresponding tests, and
diff --git a/Src/params.c b/Src/params.c
index b4179a4f4..1a2bf62d2 100644
--- a/Src/params.c
+++ b/Src/params.c
@@ -5893,6 +5893,7 @@ scanendscope(HashNode hn, UNUSED(int flags))
 		export_param(pm);
 	} else
 	    unsetparam_pm(pm, 0, 0);
+	pm = NULL;
     }
     if (hidden)
 	pm = hidden;