diff --git a/examples/tcp/tcp-validation.cc b/examples/tcp/tcp-validation.cc
index c2e98f043..cc383dd8d 100644
--- a/examples/tcp/tcp-validation.cc
+++ b/examples/tcp/tcp-validation.cc
@@ -231,10 +231,10 @@ TraceFirstDctcp(std::ofstream* ofStream, uint32_t bytesMarked, uint32_t bytesAck
             NS_LOG_WARN("now " << Now().As(Time::S) << " alpha " << alpha << " (expected <= 0.1)");
             g_validationFailed = true;
         }
-        if ((now > 7) && ((alpha > 0.09) || (alpha < 0.055)))
+        if ((now > 7) && ((alpha > 0.09) || (alpha < 0.049)))
         {
             NS_LOG_WARN("now " << Now().As(Time::S) << " alpha " << alpha
-                               << " (expected 0.09 <= alpha <= 0.055)");
+                               << " (expected 0.09 <= alpha <= 0.049)");
             g_validationFailed = true;
         }
     }
diff --git a/src/test/ns3tcp/ns3tcp-cubic-test-suite.cc b/src/test/ns3tcp/ns3tcp-cubic-test-suite.cc
index 8013a40a6..876bcfb54 100644
--- a/src/test/ns3tcp/ns3tcp-cubic-test-suite.cc
+++ b/src/test/ns3tcp/ns3tcp-cubic-test-suite.cc
@@ -348,7 +348,7 @@ Ns3TcpCubicTestCase::DoRun()
     if (m_prefix == "ns3-tcp-cubic-no-heuristic")
     {
         // Check overall min and max
-        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(1), Seconds(19), 50, 90),
+        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(1), Seconds(19), 60, 98),
                               true,
                               "cwnd outside range");
         // Time just before a reduction does not have much variation
@@ -359,7 +359,7 @@ Ns3TcpCubicTestCase::DoRun()
     else if (m_prefix == "ns3-tcp-cubic-fast-conv")
     {
         // Check overall min and max
-        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(1), Seconds(19), 50, 90),
+        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(1), Seconds(19), 60, 98),
                               true,
                               "cwnd outside range");
         // Initial convex region does not have much variation
@@ -375,7 +375,7 @@ Ns3TcpCubicTestCase::DoRun()
                               true,
                               "cwnd outside range");
         // After time 17.5, cwnd should have grown much higher
-        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(17.5), Seconds(18.5), 170, 215),
+        NS_TEST_ASSERT_MSG_EQ(CheckValues(Seconds(17.5), Seconds(18.5), 169, 215),
                               true,
                               "cwnd outside range");
     }