From 4cdedf65247a0e720f0723bcd9edb773b3f2223f Mon Sep 17 00:00:00 2001
From: drieseng <gert.driesen@telenet.be>
Date: Sun, 29 May 2022 16:59:38 +0200
Subject: [PATCH] Use cryptographically secure random number generator. Fixes
 CVE-2022-29245.

---
 src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs b/src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs
index 9de7af8fb..b7a318bb9 100644
--- a/src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs
+++ b/src/Renci.SshNet/Security/KeyExchangeECCurve25519.cs
@@ -1,5 +1,4 @@
-using System;
-using Renci.SshNet.Abstractions;
+using Renci.SshNet.Abstractions;
 using Renci.SshNet.Common;
 using Renci.SshNet.Messages.Transport;
 using Renci.SshNet.Security.Chaos.NaCl;
@@ -46,9 +45,7 @@ public override void Start(Session session, KeyExchangeInitMessage message)
             var basepoint = new byte[MontgomeryCurve25519.PublicKeySizeInBytes];
             basepoint[0] = 9;
 
-            var rnd = new Random();
-            _privateKey = new byte[MontgomeryCurve25519.PrivateKeySizeInBytes];
-            rnd.NextBytes(_privateKey);
+            _privateKey = CryptoAbstraction.GenerateRandom(MontgomeryCurve25519.PrivateKeySizeInBytes);
 
             _clientExchangeValue = new byte[MontgomeryCurve25519.PublicKeySizeInBytes];
             MontgomeryOperations.scalarmult(_clientExchangeValue, 0, _privateKey, 0, basepoint, 0);