From 3f048ca5fa1382a079e859e24897aebfffd2627f Mon Sep 17 00:00:00 2001
From: Shauren <shauren.trinity@gmail.com>
Date: Wed, 15 Mar 2017 21:41:58 +0100
Subject: [PATCH] Core/Auth: Per SRP6a protocol, terminate connection of A % N
 == 0.  This resolves another authentication bypass issue

(cherry picked from commit cmangos/mangos-wotlk@ea3e08a8123fbce0082b8aae8eb9b2541f083a9c)
---
 src/server/authserver/Server/AuthSession.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/server/authserver/Server/AuthSession.cpp b/src/server/authserver/Server/AuthSession.cpp
index 37bbade765d..3fb34ac478f 100644
--- a/src/server/authserver/Server/AuthSession.cpp
+++ b/src/server/authserver/Server/AuthSession.cpp
@@ -479,7 +479,7 @@ bool AuthSession::HandleLogonProof()
     A.SetBinary(logonProof->A, 32);
 
     // SRP safeguard: abort if A == 0
-    if (A.IsZero())
+    if ((A % N).IsZero())
         return false;
 
     SHA1Hash sha;