From 11d11524f6ef21347059123eb9dd693b604b0f52 Mon Sep 17 00:00:00 2001
From: Geoff Hutchison <geoff.hutchison@gmail.com>
Date: Tue, 19 May 2026 11:28:56 -0400
Subject: [PATCH] Fix fuzz bug - check for 0 or negative bond (tb)

Signed-off-by: Geoff Hutchison <geoff.hutchison@gmail.com>
---
 src/mcdlutil.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mcdlutil.cpp b/src/mcdlutil.cpp
index 9dbd1cdd4..82823c056 100644
--- a/src/mcdlutil.cpp
+++ b/src/mcdlutil.cpp
@@ -628,7 +628,7 @@ namespace OpenBabel {
 
   int TSingleBond::getValence() {
     int result=0;
-    if (this->tb <=NBONDTYPES) result=bondValence[this->tb-1];
+    if (this->tb >= 1 && this->tb <= NBONDTYPES) result=bondValence[this->tb-1];
     return result;
   };