diff --git a/source/FreeRTOS_ND.c b/source/FreeRTOS_ND.c
index 43c68cd6a..439c5038a 100644
--- a/source/FreeRTOS_ND.c
+++ b/source/FreeRTOS_ND.c
@@ -573,6 +573,7 @@
         IPv6_Address_t xTargetIPAddress;
         MACAddress_t xMultiCastMacAddress;
         NetworkBufferDescriptor_t * pxDescriptor = pxNetworkBuffer;
+        NetworkBufferDescriptor_t * pxNewDescriptor = NULL;
 
         if( ( pxEndPoint != NULL ) && ( pxEndPoint->bits.bIPv6 != pdFALSE_UNSIGNED ) )
         {
@@ -580,7 +581,9 @@
 
             if( pxDescriptor->xDataLength < uxNeededSize )
             {
-                pxDescriptor = pxDuplicateNetworkBufferWithDescriptor( pxDescriptor, uxNeededSize );
+                pxNewDescriptor = pxDuplicateNetworkBufferWithDescriptor( pxDescriptor, uxNeededSize );
+                vReleaseNetworkBufferAndDescriptor( pxDescriptor );
+                pxDescriptor = pxNewDescriptor;
             }
 
             if( pxDescriptor != NULL )
diff --git a/source/FreeRTOS_RA.c b/source/FreeRTOS_RA.c
index c98094752..e36d8aea0 100644
--- a/source/FreeRTOS_RA.c
+++ b/source/FreeRTOS_RA.c
@@ -138,6 +138,7 @@
         NetworkBufferDescriptor_t * pxDescriptor = pxNetworkBuffer;
         IPv6_Address_t xSourceAddress;
         BaseType_t xHasLocal;
+        NetworkBufferDescriptor_t * pxNewDescriptor = NULL;
 
         configASSERT( pxEndPoint != NULL );
         configASSERT( pxEndPoint->bits.bIPv6 != pdFALSE_UNSIGNED );
@@ -156,7 +157,9 @@
 
         if( pxDescriptor->xDataLength < uxNeededSize )
         {
-            pxDescriptor = pxDuplicateNetworkBufferWithDescriptor( pxDescriptor, uxNeededSize );
+            pxNewDescriptor = pxDuplicateNetworkBufferWithDescriptor( pxDescriptor, uxNeededSize );
+            vReleaseNetworkBufferAndDescriptor( pxDescriptor );
+            pxDescriptor = pxNewDescriptor;
         }
 
         if( pxDescriptor != NULL )
diff --git a/test/unit-test/FreeRTOS_ND/FreeRTOS_ND_utest.c b/test/unit-test/FreeRTOS_ND/FreeRTOS_ND_utest.c
index f0d0ddf93..d15d77445 100644
--- a/test/unit-test/FreeRTOS_ND/FreeRTOS_ND_utest.c
+++ b/test/unit-test/FreeRTOS_ND/FreeRTOS_ND_utest.c
@@ -722,6 +722,8 @@ void test_vNDAgeCache_NSIncorrectDataLen( void )
 
     pxDuplicateNetworkBufferWithDescriptor_ExpectAnyArgsAndReturn( NULL );
 
+    vReleaseNetworkBufferAndDescriptor_Expect( &xNetworkBuffer );
+
     vNDAgeCache();
 
     TEST_ASSERT_EQUAL( xNDCache[ xUseEntry ].ucAge, xAgeDefault - 1 );
diff --git a/test/unit-test/FreeRTOS_RA/FreeRTOS_RA_utest.c b/test/unit-test/FreeRTOS_RA/FreeRTOS_RA_utest.c
index d50af6b65..0d77637d7 100644
--- a/test/unit-test/FreeRTOS_RA/FreeRTOS_RA_utest.c
+++ b/test/unit-test/FreeRTOS_RA/FreeRTOS_RA_utest.c
@@ -149,6 +149,8 @@ void test_vNDSendRouterSolicitation_xHasLocal0( void )
 
     pxDuplicateNetworkBufferWithDescriptor_ExpectAnyArgsAndReturn( NULL );
 
+    vReleaseNetworkBufferAndDescriptor_Expect( pxNetworkBuffer );
+
     vNDSendRouterSolicitation( pxNetworkBuffer, &xIPAddress );
 }
 
@@ -188,6 +190,8 @@ void test_vNDSendRouterSolicitation_xHasLocal1( void )
 
     pxDuplicateNetworkBufferWithDescriptor_ExpectAnyArgsAndReturn( NULL );
 
+    vReleaseNetworkBufferAndDescriptor_Expect( pxNetworkBuffer );
+
     vNDSendRouterSolicitation( pxNetworkBuffer, &xIPAddress );
 }
 
@@ -223,6 +227,8 @@ void test_vNDSendRouterSolicitation_NullDesc( void )
 
     pxDuplicateNetworkBufferWithDescriptor_ExpectAnyArgsAndReturn( NULL );
 
+    vReleaseNetworkBufferAndDescriptor_Expect( pxNetworkBuffer );
+
     vNDSendRouterSolicitation( pxNetworkBuffer, &xIPAddress );
 }
 
@@ -1017,6 +1023,8 @@ void test_vRAProcess_eRAStateApply2( void )
     /*usGenerateProtocolChecksum_ExpectAnyArgsAndReturn( ipCORRECT_CRC ); */
     /*vReturnEthernetFrame_ExpectAnyArgs(); */
 
+    vReleaseNetworkBufferAndDescriptor_Expect( &xNetworkBuffer );
+
     vDHCP_RATimerReload_ExpectAnyArgs();
 
     /* pdFALSE for vRAProcessInit */