diff --git a/apps/wolfssh/common.c b/apps/wolfssh/common.c
index ac1adc4e..2d6e7693 100644
--- a/apps/wolfssh/common.c
+++ b/apps/wolfssh/common.c
@@ -392,11 +392,16 @@ int ClientPublicKeyCheck(const byte* pubKey, word32 pubKeySz, void* ctx)
         fp[0] = 0;
 
         /* Get the key type out of the key. */
-        ato32(pubKey, &sz);
-        if ((sz > pubKeySz - sizeof(word32))
-                    || (sz > WOLFSSH_CLIENT_PUBKEYTYPE_SIZE_ESTIMATE - 1)) {
+        if (pubKeySz < sizeof(word32)) {
             ret = -1;
         }
+        else {
+            ato32(pubKey, &sz);
+            if ((sz > pubKeySz - sizeof(word32))
+                        || (sz > WOLFSSH_CLIENT_PUBKEYTYPE_SIZE_ESTIMATE - 1)) {
+                ret = -1;
+            }
+        }
     }
 
     if (ret == 0) {