diff --git a/src/qt/test/paymentservertests.cpp b/src/qt/test/paymentservertests.cpp
index 67fde4033..985a8dce5 100644
--- a/src/qt/test/paymentservertests.cpp
+++ b/src/qt/test/paymentservertests.cpp
@@ -1,219 +1,220 @@
 // Copyright (c) 2009-2015 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <qt/test/paymentservertests.h>
 
 #include <amount.h>
 #include <interfaces/node.h>
 #include <qt/optionsmodel.h>
 #include <qt/test/paymentrequestdata.h>
 #include <random.h>
 #include <script/script.h>
 #include <script/standard.h>
 #include <util/strencodings.h>
 #include <util/system.h>
 
 #include <openssl/x509.h>
 #include <openssl/x509_vfy.h>
 
 #include <QFileOpenEvent>
 #include <QTemporaryFile>
 
 X509 *parse_b64der_cert(const char *cert_data) {
     std::vector<uint8_t> data = DecodeBase64(cert_data);
     assert(data.size() > 0);
     const uint8_t *dptr = data.data();
     X509 *cert = d2i_X509(nullptr, &dptr, data.size());
     assert(cert);
     return cert;
 }
 
 //
 // Test payment request handling
 //
 
 static SendCoinsRecipient handleRequest(PaymentServer *server,
                                         std::vector<uint8_t> &data) {
     RecipientCatcher sigCatcher;
     QObject::connect(server, &PaymentServer::receivedPaymentRequest,
                      &sigCatcher, &RecipientCatcher::getRecipient);
 
     // Write data to a temp file:
     QTemporaryFile f;
     f.open();
     f.write((const char *)data.data(), data.size());
     f.close();
 
     // Create a QObject, install event filter from PaymentServer and send a file
     // open event to the object
     QObject object;
     object.installEventFilter(server);
     QFileOpenEvent event(f.fileName());
     // If sending the event fails, this will cause sigCatcher to be empty, which
     // will lead to a test failure anyway.
     QCoreApplication::sendEvent(&object, &event);
 
     QObject::disconnect(server, &PaymentServer::receivedPaymentRequest,
                         &sigCatcher, &RecipientCatcher::getRecipient);
 
     // Return results from sigCatcher
     return sigCatcher.recipient;
 }
 
 void PaymentServerTests::paymentServerTests() {
     SelectParams(CBaseChainParams::MAIN);
     auto node = interfaces::MakeNode();
     OptionsModel optionsModel(*node);
     PaymentServer *server = new PaymentServer(nullptr, false);
     X509_STORE *caStore = X509_STORE_new();
     X509_STORE_add_cert(caStore, parse_b64der_cert(caCert1_BASE64));
     PaymentServer::LoadRootCAs(caStore);
     server->setOptionsModel(&optionsModel);
     server->uiReady();
 
     std::vector<uint8_t> data;
     SendCoinsRecipient r;
     QString merchant;
 
     // Now feed PaymentRequests to server, and observe signals it produces
 
     // This payment request validates directly against the caCert1 certificate
     // authority:
     data = DecodeBase64(paymentrequest1_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString("testmerchant.org"));
 
     // Signed, but expired, merchant cert in the request:
     data = DecodeBase64(paymentrequest2_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString(""));
 
     // 10-long certificate chain, all intermediates valid:
     data = DecodeBase64(paymentrequest3_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString("testmerchant8.org"));
 
     // Long certificate chain, with an expired certificate in the middle:
     data = DecodeBase64(paymentrequest4_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString(""));
 
     // Validly signed, but by a CA not in our root CA list:
     data = DecodeBase64(paymentrequest5_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString(""));
 
     // Try again with no root CA's, verifiedMerchant should be empty:
     caStore = X509_STORE_new();
     PaymentServer::LoadRootCAs(caStore);
     data = DecodeBase64(paymentrequest1_cert1_BASE64);
     r = handleRequest(server, data);
     r.paymentRequest.getMerchant(caStore, merchant);
     QCOMPARE(merchant, QString(""));
 
     // Load second root certificate
     caStore = X509_STORE_new();
     X509_STORE_add_cert(caStore, parse_b64der_cert(caCert2_BASE64));
     PaymentServer::LoadRootCAs(caStore);
 
     QByteArray byteArray;
 
     // For the tests below we just need the payment request data from
     // paymentrequestdata.h parsed + stored in r.paymentRequest.
     //
     // These tests require us to bypass the following normal client execution
     // flow shown below to be able to explicitly just trigger a certain
     // condition!
     //
     // handleRequest()
     // -> PaymentServer::eventFilter()
     //   -> PaymentServer::handleURIOrFile()
     //     -> PaymentServer::readPaymentRequestFromFile()
     //       -> PaymentServer::processPaymentRequest()
 
     // Contains a testnet paytoaddress, so payment request network doesn't match
     // client network:
     data = DecodeBase64(paymentrequest1_cert2_BASE64);
     byteArray = QByteArray((const char *)data.data(), data.size());
     r.paymentRequest.parse(byteArray);
     // Ensure the request is initialized, because network "main" is default,
     // even for uninitialized payment requests and that will fail our test here.
     QVERIFY(r.paymentRequest.IsInitialized());
     QCOMPARE(PaymentServer::verifyNetwork(*node, r.paymentRequest.getDetails()),
              false);
 
     // Expired payment request (expires is set to 1 = 1970-01-01 00:00:01):
     data = DecodeBase64(paymentrequest2_cert2_BASE64);
     byteArray = QByteArray((const char *)data.data(), data.size());
     r.paymentRequest.parse(byteArray);
     // Ensure the request is initialized
     QVERIFY(r.paymentRequest.IsInitialized());
     // compares 1 < GetTime() == false (treated as expired payment request)
     QCOMPARE(PaymentServer::verifyExpired(r.paymentRequest.getDetails()), true);
 
     // Unexpired payment request (expires is set to 0x7FFFFFFFFFFFFFFF = max.
     // int64_t):
     // 9223372036854775807 (uint64), 9223372036854775807 (int64_t) and -1
     // (int32_t)
     // -1 is 1969-12-31 23:59:59 (for a 32 bit time values)
     data = DecodeBase64(paymentrequest3_cert2_BASE64);
     byteArray = QByteArray((const char *)data.data(), data.size());
     r.paymentRequest.parse(byteArray);
     // Ensure the request is initialized
     QVERIFY(r.paymentRequest.IsInitialized());
     // compares 9223372036854775807 < GetTime() == false (treated as unexpired
     // payment request)
     QCOMPARE(PaymentServer::verifyExpired(r.paymentRequest.getDetails()),
              false);
 
     // Unexpired payment request (expires is set to 0x8000000000000000 > max.
     // int64_t, allowed uint64):
     // 9223372036854775808 (uint64), -9223372036854775808 (int64_t) and 0
     // (int32_t)
     // 0 is 1970-01-01 00:00:00 (for a 32 bit time values)
     data = DecodeBase64(paymentrequest4_cert2_BASE64);
     byteArray = QByteArray((const char *)data.data(), data.size());
     r.paymentRequest.parse(byteArray);
     // Ensure the request is initialized
     QVERIFY(r.paymentRequest.IsInitialized());
     // compares -9223372036854775808 < GetTime() == true (treated as expired
     // payment request)
     QCOMPARE(PaymentServer::verifyExpired(r.paymentRequest.getDetails()), true);
 
     // Test BIP70 DoS protection:
-    uint8_t randData[BIP70_MAX_PAYMENTREQUEST_SIZE + 1];
-    GetRandBytes(randData, sizeof(randData));
+    auto randdata =
+        FastRandomContext().randbytes(BIP70_MAX_PAYMENTREQUEST_SIZE + 1);
+
     // Write data to a temp file:
     QTemporaryFile tempFile;
     tempFile.open();
-    tempFile.write((const char *)randData, sizeof(randData));
+    tempFile.write((const char *)randdata.data(), randdata.size());
     tempFile.close();
     // compares 50001 <= BIP70_MAX_PAYMENTREQUEST_SIZE == false
     QCOMPARE(PaymentServer::verifySize(tempFile.size()), false);
 
     // Payment request with amount overflow (amount is set to 21000001 BCH):
     data = DecodeBase64(paymentrequest5_cert2_BASE64);
     byteArray = QByteArray((const char *)data.data(), data.size());
     r.paymentRequest.parse(byteArray);
     // Ensure the request is initialized
     QVERIFY(r.paymentRequest.IsInitialized());
     // Extract address and amount from the request
     QList<std::pair<CScript, Amount>> sendingTos = r.paymentRequest.getPayTo();
     for (const std::pair<CScript, Amount> &sendingTo : sendingTos) {
         CTxDestination dest;
         if (ExtractDestination(sendingTo.first, dest))
             QCOMPARE(PaymentServer::verifyAmount(sendingTo.second), false);
     }
 
     delete server;
 }
 
 void RecipientCatcher::getRecipient(const SendCoinsRecipient &r) {
     recipient = r;
 }