From 4ff0683a166bce841361901d2b41152afa998e8a Mon Sep 17 00:00:00 2001
From: John Safranek <john@wolfssl.com>
Date: Tue, 28 Jun 2022 11:38:07 -0700
Subject: [PATCH] RSA Userauth Initialization

For RSA user authentication, initialize the arrays used to store the
check value and the signature before loading and comparing them.
(ZD 14412)
---
 src/internal.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/internal.c b/src/internal.c
index 54d417c4..afd9bf20 100644
--- a/src/internal.c
+++ b/src/internal.c
@@ -4152,6 +4152,7 @@ static int DoUserAuthRequestRsa(WOLFSSH* ssh, WS_UserAuthData_PublicKey* pk,
     }
 
     if (ret == WS_SUCCESS) {
+        WMEMSET(checkDigest, 0, MAX_ENCODED_SIG_SZ);
         ret = wc_InitRsaKey(key_ptr, ssh->ctx->heap);
         if (ret == 0) {
             ret = WS_SUCCESS;
@@ -4243,6 +4244,7 @@ static int DoUserAuthRequestRsa(WOLFSSH* ssh, WS_UserAuthData_PublicKey* pk,
         encDigest = s_encDigest;
 #endif
         {
+            WMEMSET(encDigest, 0, MAX_ENCODED_SIG_SZ);
             encDigestSz = wc_EncodeSignature(encDigest, digest,
                                          wc_HashGetDigestSize(enmhashId),
                                          wc_HashGetOID(enmhashId));