diff --git a/src/hb-aat-layout-kerx-table.hh b/src/hb-aat-layout-kerx-table.hh
index 6b61186a9..4e6c6e405 100644
--- a/src/hb-aat-layout-kerx-table.hh
+++ b/src/hb-aat-layout-kerx-table.hh
@@ -260,7 +260,7 @@ struct KerxSubTableFormat1
 	  depth = 0; /* Probably not what CoreText does, but better? */
       }
 
-      if (Format1EntryT::performAction (entry))
+      if (depth && Format1EntryT::performAction (entry))
       {
 	unsigned int tuple_count = MAX (1u, table->header.tuple_count ());
 
diff --git a/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-shape-fuzzer-5691469793329152 b/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-shape-fuzzer-5691469793329152
new file mode 100644
index 000000000..6c7390002
Binary files /dev/null and b/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-shape-fuzzer-5691469793329152 differ