diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 9ff384d0..3dbd3fab 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -1104,7 +1104,7 @@ parse_hash_fingerprint(const char *str, int nbytes, int msglevel, struct gc_aren
     ALLOC_OBJ_CLEAR_GC(ret, struct verify_hash_list, gc);
 
     char term = 0;
-    int byte;
+    unsigned int byte;
 
     while (*cp && i < nbytes)
     {