diff --git a/src/ssl.c b/src/ssl.c
index 6c5841b51..fc0c03189 100644
--- a/src/ssl.c
+++ b/src/ssl.c
@@ -28482,8 +28482,8 @@ int wolfSSL_i2d_RSAPublicKey(WOLFSSL_RSA *rsa, const unsigned char **pp)
         XFREE(der, NULL, DYNAMIC_TYPE_TMP_BUFFER);
         return ret;
     }
-
-    *pp = der;
+    if((pp != NULL) && (ret >= 0))
+        *pp = der;
     return ret;
 }
 #endif /* #if !defined(HAVE_FAST_RSA) */
diff --git a/tests/api.c b/tests/api.c
index 88e3f8338..e6e8e6552 100644
--- a/tests/api.c
+++ b/tests/api.c
@@ -19180,6 +19180,7 @@ static void test_wolfSSL_RSA_DER(void)
     {
         AssertNotNull(d2i_RSAPublicKey(&rsa, &pub[i].der, pub[i].sz));
         AssertNotNull(rsa);
+        AssertIntEQ(i2d_RSAPublicKey(rsa, NULL), pub[i].sz);
         buff = NULL;
         AssertIntEQ(i2d_RSAPublicKey(rsa, &buff), pub[i].sz);
         AssertNotNull(buff);