diff --git a/src/hb-ot-layout-gsubgpos.hh b/src/hb-ot-layout-gsubgpos.hh
index 33b78b1fb..796a29d0b 100644
--- a/src/hb-ot-layout-gsubgpos.hh
+++ b/src/hb-ot-layout-gsubgpos.hh
@@ -1248,7 +1248,7 @@ static void context_closure_recurse_lookups (hb_closure_context_t *c,
   for (unsigned int i = 0; i < lookupCount; i++)
   {
     unsigned seqIndex = lookupRecord[i].sequenceIndex;
-    if (seqIndex > inputCount) continue;
+    if (seqIndex >= inputCount) continue;
 
     hb_set_t *pos_glyphs = hb_set_create ();
 
diff --git a/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-subset-fuzzer-6173520787800064 b/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-subset-fuzzer-6173520787800064
new file mode 100644
index 000000000..035dd72f1
Binary files /dev/null and b/test/fuzzing/fonts/clusterfuzz-testcase-minimized-hb-subset-fuzzer-6173520787800064 differ